Question

problem 19:
(first taught in
lesson 42)
find x.
after you enter your answer press go.

Explanation:

Step1: Use the property of isosceles triangle

In an isosceles triangle, angles opposite equal sides are equal. So \(3x + 9=4x - 3\).

Step2: Solve the equation

Subtract \(3x\) from both sides: \(3x+9 - 3x=4x - 3-3x\), which gives \(9=x - 3\).
Then add \(3\) to both sides: \(9 + 3=x-3 + 3\).

Answer:

\(x = 12\)