Question

problem 22: (first taught in lesson 16) ∠a and ∠d are supplementary. if m∠a = 9y - 19 and m∠d = 3y - 5, find m∠a. after you enter your answer press go. m∠a =

Explanation:

Step1: Use supplementary - angle property

$(9y - 19)+(3y - 5)=180$

Step2: Combine like - terms

$9y+3y-19 - 5 = 180$
$12y-24 = 180$

Step3: Isolate the variable term

$12y=180 + 24$
$12y=204$

Step4: Solve for y

$y=\frac{204}{12}=17$

Step5: Find m∠A

$m\angle A=9y - 19$
Substitute $y = 17$: $m\angle A=9\times17-19$
$m\angle A = 153-19=128$

Answer:

$128$