Hopes this helps:
Answer: x = -10/7
1. Simplify 2 • 2 to 4
4 + 7x + 6 = 0
2. Simplify 4 + 7x + 6 to 7x + 10.
7x + 10 = 0
3. Subtract 10 from both sides.
7x = -10
4. Divide both sides by 7.
X = -10/7
The equation for this is a^2+b^2=c^2 so your equation would be 7^2+20^2=X
So you square the 7 and the 20 then take the square root of X and you get
X=21.19
:)
the answer is in the picture