Question

find the value of x.
c (2x + 9)°
(7x)°
e
d
h
f
g
x =

Explanation:

Step1: Identify angle - relationship

The two angles $(7x)^{\circ}$ and $(2x + 9)^{\circ}$ are complementary since they form a right - angle (90°). So, we set up the equation $7x+(2x + 9)=90$.

Step2: Simplify the left - hand side of the equation

Combine like terms: $7x+2x+9 = 9x+9$. So the equation becomes $9x + 9=90$.

Step3: Isolate the variable term

Subtract 9 from both sides of the equation: $9x+9 - 9=90 - 9$, which simplifies to $9x=81$.

Step4: Solve for x

Divide both sides of the equation by 9: $\frac{9x}{9}=\frac{81}{9}$, so $x = 9$.

Answer:

$9$