Question

Elimination would be the most efficient way to solve which of the following systems?


a. 4x+3y=6

3y=5


b. 2x+3y=12

5x-5y=21


c. y=2x

x+3y=5


d. x+y=7

x-y=12

Answer 1

Think: What does "elimination by addition/subtraction" mean?

Answer 2

i really dont know what that means but i think its b.

Answer 3

It'd be far more efficient (and produce higher grades) to learn this and other methods instead of guessing which possible answer is the correct one.

suppose I were to write out a system of linear equations as

x + y = 7
x - y = 12

Simply add together all the x terms, all the y terms, and all the constant terms.
What do you get?

Answer 4

can you explain it because im a hard learner or just give me the answer

Answer 5

This material is well within your ability to learn.
x+x = ?
y - y =?
7+12 = ?

Answer 6

2x
no y
19

Answer 7

Right. Therefore,

x + y = 7
x - y = 12
---------
2x = 19
Solve this for x.

Answer 8

thank you so it d.

Answer 9

Yes.