Question

Alright, so I need to solve these with elimination or substitution, and I am having a hard time.

2x+y=25
3y=2x-13

and

y-2x=-8
4y+13x=10

Thank you in advance if you help. ;u;

Answer 1

you're welcome in advance as am going to help! ;)

Answer 2

well calculate y from eqn 1 and eqn 2..
equate them.. you'll find x thus..
same with second ques..
if you didnt get it please tell me..

Answer 3

I'm not sure I'm understanding. I work better when I can see the steps of a problem.

Answer 4

in first ques..
from eqn 1,,
y= 25 -2x
from eqn 2,,
y=(2x-13)/3
thus 25-2x = (2x-13)/3

calculate x from here..put that in any of the eqns and solve for y
this is substitution method

for elimination,,multiply both sides of 1st eqn by 3 and subtract it from 2nd ..
you'll get this
6x + 3y -3y = 75 -2x +13
=> 6x = 75 - 2x +13
x= ?

now if this is clear can you show me 2nd ques yourself

Answer 5

For the first question, I am using Substitution method:
2x + y = 25 -------- eqn (1)
3y = 2x - 13--------eqn (2)

First re-arrange eqn (2) to look like eqn (1)
2x - 3y = 13 ------eqn (3)

Make y the subject for eqn (1)
y = 25 - 2x --------eqn (4)

Put the answer of y in eqn (4) into anywhere you see y in eqn (3)
2x - 3(25 - 2x) = 13

Expand the bracket and solve for x
2x - 75 + 6x = 13

Group like-terms on one side and solve for x
2x + 6x = 13 + 75
8x = 88

Divide both sides by 8 to make x stand alone.
\[x = \frac{88}{8}\]
x = 11


Put the answer of x (x = 11) into any equation above and solve for y.
I am choosing eqn(3)
2x - 3y = 13 ------eqn (3)
2(11) - 3y = 13
22 - 3y = 13
-3y = 13 - 22
-3y = -9

Divide both sides by -3 to allow y to standalone
\[y = \frac{-9}{-3}\]
y = 3

Hence, x = 11 and y = 3

Follow the same procedure and solve the second question.

Answer 6

Thanks alot! This helps! :D

Answer 7

You welcome