How do you solve the following linear system: # 5x+8y=1, -2x+3y=4, #?

1 Answer
Shubh
Mar 30, 2018

It can be solved by,
- Elimination method.
- Substitution method.

Explanation:

1)By elimination method,
#5x+8y=1--(I) eqn#
#2x+3y=4--(II)eqn#
multiply eqn (I) by 2 & eqn (II) by 5,
#10x+16y=2--(3)eqn#
#10x+15y=20--(4)eqn#
after solving further, will give
#y=-18#
so, #x=29#

2)By substitution method,
#5x+8y=1#
#x=(1-8y)/5--(1)#
#2x+3y=4--(2)#
put value of x in eqn(2)
#2((1-8y)/5)+3y=4#
#(2-16y)/5+3y=4#
#(2-16y+15y)/5=4#
#2-y=20#
#y=-18#
so, #x=(1-8(-18))/5#
#x=(1+144)/5#
#x=145/5#
#x=29#

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