Using the formula r = d/t, where d is the distance in miles, r is the rate, and t is the time in hours, at which rate must you travel to cover 212.5 miles in 2.5 hours?

a- 71 mph
b- 106 mph
c- 150 mph
d- 85 mph ?

What is the simplified form of the following expression?

-(8d - 3w)

a. 8d + 3w
b. 8d - 3w
c. -8d + 3w ?
d. -8d - 3w

What is the simplified form of the following expression?

12(6^2 / (5^2 - 4^2) + 7))

a. 12.6
b. 195
c. 33.8
d. 132 ?

What is the simplified form of the following expression?

(-28st)/(-4s)

a. -7t
b. 7t ?
c. -7s
d. 7s

2 answers

all ok , but.......

12(6^2 / (5^2 - 4^2) + 7))

the number of right-sided brackets must match the number of left-sided brackets. You have 2 going right, 3 going left.

Even Wolfram didn't like it , and fixed it for you
http://www.wolframalpha.com/input/?i=12%286%5E2+%2F+%285%5E2+-+4%5E2%29+%2B+7%29%29+
Thank you, the extra bracket was a typo. So, is my answer correct on that one?