Question

if angle abc = 70 degrees then find the value of x
(3x + 15)°
(x + 7)°

Explanation:

Step1: Set up angle - sum equation

Since $\angle ABC=\angle ABD+\angle DBC$, we have the equation $70=(3x + 15)+(x + 7)$.

Step2: Combine like - terms

First, simplify the right - hand side of the equation: $(3x + 15)+(x + 7)=3x+x+15 + 7=4x+22$. So the equation becomes $4x+22 = 70$.

Step3: Isolate the variable term

Subtract 22 from both sides of the equation: $4x+22-22=70 - 22$, which simplifies to $4x=48$.

Step4: Solve for x

Divide both sides of the equation by 4: $\frac{4x}{4}=\frac{48}{4}$, so $x = 12$.

Answer:

$x = 12$