Given:

He does mistake in the order of giving preference.
We should give preference in the order, division, multiplication, addition, subtraction.
But, he gave the first preferrence to the subtraction.
72-8=64
Next, he used division
64/2=32
Next he adds 32 with 8.
So, he gets 50.
But the actual simplification is,
Simplifying we get,

Hence, the correct value of the expression is 86.
Answer:
-32p+56
Step-by-step explanation:
-8*4p=-32p
-7*-8=56(negative times negative =positive)
-32p+56
Pythagorean Theorem is for triangles not circles.
The equation of a circle is (x - h)² + (y - k)² = radius² where (h, k) is the center.
Plug in your given information and simplify.
(x - (- 1))² + (y - 2)² = (3)²
(x + 1)² + (y - 2)² = 9 is your equation.