Answer:
x = 24
Explanation:
The formula for determining the sum of interior angles is:
![(n-2) * 180](https://img.qammunity.org/2023/formulas/mathematics/high-school/gcv4s9ynvx94b3c92d12ipw0ykrlfjwika.png)
![4 * 180 = 720](https://img.qammunity.org/2023/formulas/mathematics/high-school/1hzskq3p6crkak8xviep3js6iggfpo3xmb.png)
Therefore to determine an equation for x, we must add up all the interior angle equations and set them equal to 720.
![(2x+3) +(3x+12) + (7x+14) + (9x+2) + (4x+8) + (3x+9) = 720\\28x + 48 = 720\\28x = 672\\x = 24](https://img.qammunity.org/2023/formulas/mathematics/high-school/z1i20t4unqi37f4k5deoxjefivr8gu9iz9.png)
The equation and answer above shows how to find x, which equals 24.