The function is:
f ( x ) = x² - x - 72
This is a quatdratic function. So we can find the zeroes of the function with the formula:
x 1/2 = ( - b +/- √(b² - 4 ac) ) / ( 2a )
And we have: a = 1, b = - 1 and c = - 72
x 1/2 = ( 1 +/- √((-1)² - 4 · 1· ( - 72 )) ) / 2
x 1/2 = ( 1 +/- √( 1 + 288 ) ) / 2
x 1/2 = ( 1 +/- √289 ) / 2
x 1/2 = ( 1 +/- 17 ) / 2
x 1 = ( 1 - 17 ) 2 = - 16 / 2 = - 8
x 2 = ( 1 + 17 ) / 2 = 18 / 2 = 9
Answer: The zeroes are - 8 and 9.
Answer:
I think its 8. SORRY IF WRONG
Step-by-step explanation:
The answer would be the first choice. 
Explanation: The reason for this is that the question was pretty much just asking what the area of the resulting two-dimensional cross section would be -the shape in gray- (which can be found by using the formula 
. To add on, since the dimensions of the shape are already given (5 and 3) all you've to do is multiply: 3*5=15
That's how you get to the answer.
I think the answer is A. But I’m not fully sure
7a+7b+77
I I hope this helps you
