How do you solve the following system: 5x + 8y = -2, 3x - 4y = -105x+8y=−2,3x−4y=−10?

1 Answer
EZ as pi
May 10, 2016

x = -2 and y = 1x=−2andy=1

Explanation:

For the elimination method. the coefficients of one of the variable should be the same. It is fantastically easier if they can become additive inverses - same number, different signs. +5 and - 5 add to 0.

" "5x + 8y = -2 ..................." equ A"
" " 3x - 4y = -10....................."equ B"
B xx 2: " "6x - 8y = -20 .................... "equ C"

A + B:" " 11x " "= -22
" " x = -2

Substitute in A: 5(-2) + 8y= -2 =
" "-10+8y = -2
" " 8y = -2 + 10
" " 8y = 8
" " y = 1

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