Which equation represents the following word problem:
A car is traveling twice as fast as a truck. If their combined speed is 105 miles per hour, find the speed of the car and find the speed of the truck. Please explain.

A. 3s = 105

B. s + s = 105

C. s = 105

D. s(2s) = 105

Arianna is buying plants for her garden. she buys 15 flowering plants for $96. pink flowering plants sell for $8, and purple flowering plants sell for $5. how many pink flowering plants did arianna buy? i figured out the answer! the answer is 7. 8x +5y = 96 plug in 7 for x 8 (7) + 5y = 96 56 + 5y = 96 subtract 56 from both sides 5y/y = 40/5 y = 8 she bought 7 pink and 8 purple plants

Darian wants to build a regulation size pool table that is 9 feet in length. he plans he ordered are 18 by 36 inches. what is the scale factor of the dilation he must use to build a regulation pool table

Identify the expression equivalent to 4(x + x + 7) − 2x + 8 − 4 by substituting x = 1 and x = 2.