Question

Help with this system of equations!! (explain step by step)

Answer 1

Hi

4x+7y=41

x-7y=-16

We need to solve x-7y=-16 for x

So let's start by adding 7y to both sides

x-7y+7y=-16+7y

x= 7y-16

Now substitute 7y-16 for x in 4x+7y=41

4x+7y=41

4(7y-16)+7y=41

35y-64=41

Add 64 to both sides so we can eliminate the other 64

35y-64+64=41+64

35y=105

We need to divide 35 to both sides so we find the value for y

35y/35=105/35

y=3

Now we have the y value, with they y value we can also find the x value by

substitute 3 for y in x=7y-16

x=7y-16

x=7(3)-16

x= 21-16

x= 5

Answer: x=5 and y=3

              ( 5,3)

I hope that's help:0

Answer 2

You can add the two equations together, this way you get:
5x = 25
You divide by 5:
x = 5

Now you just have to use this number in one of the original equations to get y:
x - 7y = -16
5 - 7y = -16 /subtract 5
-7y = -21 /divide by 7
-y = -3 /multiply with -1
y = 3