Question

(c) problem 18: (first taught in lesson 43)
find x.
after you enter your answer press go.
x =

Explanation:

Step1: Use angle - side relationship

Since the two angles are equal ($40^{\circ}$ each), the sides opposite them are equal. So, $5x - 8=2x + 7$.

Step2: Isolate x - terms

Subtract $2x$ from both sides: $(5x - 2x)-8=(2x - 2x)+7$, which simplifies to $3x-8 = 7$.

Step3: Isolate the constant

Add 8 to both sides: $3x-8 + 8=7 + 8$, resulting in $3x=15$.

Step4: Solve for x

Divide both sides by 3: $\frac{3x}{3}=\frac{15}{3}$, so $x = 5$.

Answer:

$x = 5$