While plotting graphs, users often need to find out or predict an unknown value relative to the present values. This allows them to forecast a result based on the existing data. In this article, we will show how to find unknown value on ** Excel** graph.

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## 4 Ways to Find Unknown Value on Excel Graph

In this article, we will discuss 4 effective ways to find an unknown value in an ** Excel** graph. Firstly, we will use

**. Secondly, we will use**

*the TREND function***. Then, we will opt for**

*the Trendline equation***to find the unknown value. Finally, we will use**

*the FORECAST function***to find the unknown value.**

*the GROWTH function*### 1. Using TREND Function

** The TREND function** returns values that have a linear trend. In this method, we will use the function to find the unknown

**value based on a known**

*Y***value.**

*X***Steps:**

- Firstly, select the
cell and write the following formula,*D10*

`=TREND(D5:D9,C5:C9,C10)`

- Hit
.*Enter*

- Consequently, we will have our unknown value and can plot it.

**Read More:** **How to Get Y Equation on Excel Graph (6 Ways)**

### 2. Applying Trendline Equation

A trendline shows the changeling trend of data. This line will either have linear or nonlinear characteristics. We will mark out the trendline equation in this case and then find the unknown value.

**Steps:**

- Firstly, select the cells containing the known
and*X**Y* - In our case, the cells are in the range
*(*.**C5:D9**) - Then, go to the
tab in the ribbon.*Insert* - From there, choose the
command.*Insert Scatter(X,Y) or Bubble Chart* - Finally, from the drop-down select a scatter plot.
- Consequently, a chart will be plotted.

- Then, click the
sign to the right of the chart.*“Plus”* - Add a trendline by checking the
box.*Trendline* - As a result,
will add a trendline to the plot.*Excel*

- After that, select any of the data points.
- Then, from there go to the
.*Trendline Options* - Finally, check the
box.*“Display Equation on chart”* - As a result, the equation of the chart will be shown on the screen.

- Then, replicate the trendline formula in the
cell as follow,*D10*

`=2*C10+200`

- Finally, hit
.*Enter*

- Consequently, we will have an unknown value.

**Read More: How to Graph Two Equations in Excel (with Easy Steps)**

### 3. Applying FORECAST Function

** The FORECAST function** utilizes current values to calculate or forecast a future value. For a specific

**x-value**, the future value is a

**y-value**. The future value is projected using linear regression using the known

**x-values**and

**y-values**for the current values.

**Steps:**

- To begin with, select the
cell and write the following formula,*D10*

`=FORECAST(C10,D5:D9,C5:C9)`

- Then, hit the
button.*Enter*

- As a result, we will have the unknown value and can plot it on the graph.

**Read More: How to Display Equation of a Line in Excel Graph (2 Easy Ways)**

### 4. Using GROWTH Function

** The GROWTH function** uses data that is already available to calculate expected exponential growth. By leveraging pre-existing

**x-values**and

**y-values**,

**returns the**

*the GROWTH function***y-values**for a set of new

**x-values**that you specify.

**Steps:**

- To start with, choose the
cell and write the following formula,*D10*

`=GROWTH(D5:D9,C5:C9,C10)`

- Then, press the
button.*Enter*

- As a result, we will get the unknown value and can plot it on the graph.

## How to Interpolate in Excel

Data interpolation is a technique for creating a simple function from a discrete data collection that passes through the specified data points. Finding the data points between the given data points is made easier by doing this.

**Steps:**

- To start with, choose the
cell and write the following formula,*G5*

`=D6+(G4-C6)*(D7-D6)/(C7-C6)`

- Then, hit the
button.*Enter*

- As a result, we will get the interpolated value.

**Read More: How to Find the Equation of a Line in Excel (With Quick Steps)**

## Conclusion

In this article, we have talked about ** 4** effective ways to find unknown value in an

**graph. These methods will allow users to properly predict a y-value with a specific x-value. If you find it useful, please let us know in the comment section below and share any recommendations and thoughts regarding this or any other content of ours. Thank you for your time. Follow**

*Excel***ExcelDemy.com**for more articles like this.