How do you solve the system 4x-5y=-43 , 6x+71=y?

1 Answer

Answer:

#x = 12 and y = 143#

Equate your #y# value to the first equation.*

Cancel out #5y# and find the value of #x#

Substitute the value for #x# into either of the two equations and solve for #y#

Explanation:

Transpose #4x - 5y = -43" "# into #" "5y = 4x + 43#
Multiply the second equation, #" "y = 6x + 71" "# by #" "5# to get:

#5y = 30x+355#

*You'll end up with two equations:

#5y = 4x + 43#
And
#5y = 30x + 355#

Thus,
#4x + 43 = 30x + 355#

Transpose your variables and constants and you'll get:

#30x - 4x = 355 - 43#

#26x = 312#

#x = 312/26#

# x = 12#

Solve for #y# since #x = 12,#

Use either of the two equations given, I'll use #y = 6x + 71#

#y = (6 x 12) + 71#

#y = 143#

#x = 12 and y = 143#