Question

help me pls: using substitution
-2x+y=7
-x+3y=11

Answer 1

muliply eq. 2 by -2 ===> -2x+y=7 , 2x-3y=-22 ===> sum both ==> -2y = -15 ===> y=15/2 ===> sybtitute in eq 1 ==> -2x+15/2=7 ==> x=1/4

Answer 2

can you show me the solution pls?

Answer 3

ok, I'll carry out that.

Answer 4

Just get one equation in terms of a variable and plug that equation in wherever you see that variable in the second equaiton

Answer 5

-2x+y=7

so
y=7+2x

then we replace the y of second equation with 7+2x because it is equal to y.

-x+3(7+2x)=11 ----> multiply 7+2x by 3

-x+21+6x=11 -----> add the x and transfer 21 to other side

5x = -10 ---------> devide both side by 5

x = -2

now substitute the value of x to any equation to get the value of y

-2(-2)+y=7 ----> multiply
4+y = 7 -------> transfer 4 to other side

y = 3


so x = -2 and y = 3

:-)

Answer 6

hope i have helped

:-)

Answer 7

checked your work; seems good to me :)

Answer 8

i get the same too