Which of the following are possible ways to eliminate a variable by multiplying first?

−x + 4y = 5
9x − 3y = 21

a. multiply the first equation by 3 and the second equation by 4.
b. multiply the first equation by 4 and the second equation by 3.
c. multiply the first equation by 3 and the second equation by 9.
d. multiply the first equation by 9 and the second equation by 4.
e. multiply the second equation by 9.
f. multiply the first equation by 9.

Each equation given below describes a parabola. which statement best compares their graphs? x = 2y^2 x = 8y^2

Which region represents the solution to the given system of inequalities? |-0.5x+y23 | 1.5x+ys-1 5 4 -3 -2 -1 1 2 3 4

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling