Question

Please answer quickly!!!

Which constants can be multiplied by the equations so one variable will be eliminated when the systems are added together? 5x + 13y = 232 12x + 7y = 218
a) The first equation can be multiplied by –13 and the second equation by 7 to eliminate y.
b) The first equation can be multiplied by 7 and the second equation by 13 to eliminate y.
c) The first equation can be multiplied by –12 and the second equation by 5 to eliminate x.
d) The first equation can be multiplied by 5 and the second equation by 12 to eliminate x.

Answer 1

Explanation:

5x + 13y = 232

12x + 7y = 218

For each choice:

a) The first equation can be multiplied by –13 and the second equation by 7 to eliminate y. So we have

- 65x - 169y = - 3016

84x + 49y = 1526

Can not eliminate x and y.

b) The first equation can be multiplied by 7 and the second equation by 13 to eliminate y. So we have

35x + 91 y = 1624

156x + 91y = 2834

Can not eliminate x and y if we ADD.

(If we subtract, this is Yes)

c) The first equation can be multiplied by –12 and the second equation by 5 to eliminate x.

-60x - 156y = - 2784

60x + 35y = 1090

The answer is YES

d) The first equation can be multiplied by 5 and the second equation by 12 to eliminate x.

25x + 65y = 1160

144x + 84y = 2616

Can not eliminate x and y

The final answer is C

Answer 2

Explanation:

5x + 13y = 232

12x + 7y = 218

For each choice:

a) The first equation can be multiplied by –13 and the second equation by 7 to eliminate y. So we have

- 65x - 169y = - 3016

84x + 49y = 1526

Can not eliminate x and y.

b) The first equation can be multiplied by 7 and the second equation by 13 to eliminate y. So we have

35x + 91 y = 1624

156x + 91y = 2834

Can not eliminate x and y if we ADD.

(If we subtract, this is Yes)

c) The first equation can be multiplied by –12 and the second equation by 5 to eliminate x.

-60x - 156y = - 2784

60x + 35y = 1090

The answer is YES

d) The first equation can be multiplied by 5 and the second equation by 12 to eliminate x.

25x + 65y = 1160

144x + 84y = 2616

Can not eliminate x and y

The final answer is C