Analyzing One-Variable Relationships in Context

From the figure, we can see that the measure of

∠ A

is

7 0^{\circ}

and that the measure of

∠ B

is

3 x + 7^{\circ} .

Since the measures are equal, we can write an equation.

7 0^{\circ} = 3 x + 7^{\circ}

We will now solve the equation by using inverse operations.

7 0^{\circ} = 3 x + 7^{\circ}

LHS - 7^{\circ} = RHS - 7^{\circ}

6 3^{\circ} = 3 x

RearrangeEqnRearrange equation

3 x = 6 3^{\circ}

LHS / 3 = RHS / 3

x = 2 1^{\circ}

Exercise 1.3 - Solution