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1 vote
Solve
3x + 4y = 8
-2X + 5y = 3

User Rajnesh
by
6.3k points

2 Answers

5 votes

Answer: x = 28/33, y = 25/23

( 28/23, 25/23)

Explanation:

3x + 4y = 8 ----------------------(1)

-2x + 5y = 3 ---------------------(2)

Using elimination method

Consider the coefficient of y in equation 1 and 2

Therefore multiply as follows

(1) x 5 -------- 15x + 20y = 40.

(2) x 4 -------- -8x + 20y = 12

Therefore carry out subtraction on the two equations

23x + 0y = 28

23x = 28

x = 28/23.

Now substitute for x in any of the equations above to get y

3(28/23) +4y = 8

84/23 +4y = 8

Multiply through by 23 to have s simple linear equation

84 + 92y = 184

Collect like terms

92y = 184 - 84

92y = 100

y = 100/92

Reduce to lowest term by dividing by 4

y = 25/33.

(28/23, 25/23)------ solution

Check

Substitute for x and y values in any equations above.

3(28/23) + 4(25/23)

84/23 + 100/23

Resolved into fraction with 23 as the common LCM

184/23

= 8

User Roo
by
6.3k points
2 votes
(x,y) = 28/23, 25/23)
User Shevron
by
6.0k points