Question

A student is trying to solve the system of two equations given below:

Equation P: a + b = 6
Equation Q: 4a + 2b = 19

Which of the following steps can be used to eliminate the a term?


-1(4a+2b=19)
-4(4a+2b=19)
-4(a+b=6)
4(a+b=6)

Answer 1

Answer: -4(a+b=6)

Step by Step Explanation: I have to got right now so I can't explain it.

Answer 2

I wonder why my answer was deleted. it was correct.

so if we wanted to cancel the terms, we would try to get the smaller term to be a negative form of the bigger one
we have the terms
a and b and
4a and 2b
to cancel the b's we would have to multiply b by -2
to cancel the a's we would have to multiply the a's by -4
to keep the truth of the sentence, we have to do that to the whole equation

so we see that there is no multiplying by -2 but there is multiplying by -4 so that is the answer

the one that is : -4(a+b=6) is the answer