How do you solve the simultaneous equations #3x + 4y = 7# and #5x - 2y = 16#?

1 Answer
Jul 22, 2015

Answer:

#(x, y) = (3, -1/2)#

Explanation:

[1]#color(white)("XXXX")##3x+4y = 7#
[2]#color(white)("XXXX")##5x-2y = 16#

Multiply [2} by 2 giving
[3]#color(white)("XXXX")##10x-4y = 32#

Add [1] and [3]
[4]#color(white)("XXXX")##13x = 39#

Divide both sides by 13
[5]#color(white)("XXXX")##x = 3#

Substitute #3# for #x# in [1]
[6]#color(white)("XXXX")##3(3) +4y = 7#

Simplify
[7]#color(white)("XXXX")##4y = -2#

[8]#color(white)("XXXX")##y = -1/2#