Question

find the value of a.
show your work here
(-10a - 16)°
(-3a + 15)°

Explanation:

Step1: Set up equation

Since the two - angle measures add up to 90° (right - angle), we have the equation $(-10a - 16)+(-3a + 15)=90$.

Step2: Combine like terms

Combining the $a$ terms and the constant terms, we get $(-10a-3a)+(-16 + 15)=90$, which simplifies to $-13a-1 = 90$.

Step3: Isolate the variable term

Add 1 to both sides of the equation: $-13a-1 + 1=90 + 1$, resulting in $-13a=91$.

Step4: Solve for $a$

Divide both sides by - 13: $a=\frac{91}{-13}$. So, $a=-7$.

Answer:

$a = - 7$