Question

find the value of b.
draw
(-4b + 128)° (3b + 60)°
show your work here

Explanation:

Step1: Set up equation

Since the two angles are supplementary (they form a straight - line and their sum is 180°), we have the equation $(-4b + 128)+(3b + 60)=180$.

Step2: Combine like terms

Combine the $b$ terms and the constant terms: $-4b+3b + 128 + 60=180$, which simplifies to $-b+188 = 180$.

Step3: Solve for $b$

Subtract 188 from both sides: $-b=180 - 188=-8$. Then multiply both sides by - 1 to get $b = 8$.

Answer:

$b = 8$