Question

solve the following equation by elimination method 3x plus 4y =10,x-y =2

Answer 1

Answer:

Given:

3x+4y=10 and x-y=1

To find:

Solve this by the elimination method.

Solution:

In the elimination method, we just eliminate one variable to find the value of other.

3x+4y=10 -----(I)

x-y=1 -----------(II)

(I) + 4(II)

3x+4y=10

4x-4y=4

7x-0y = 14

7x = 14

x = 2

Put the value of x in any of the equation.

x-y=1

2-y = 1

y = 1

The solution of 3x+4y=10 and x-y=1 is (2,1)

Answer 2

For such a simple system, you can use substitution: x=y+1 from the second equation. Substitute this value of x in the first equation to the effect that

3(y+1)+4y=10. this simplifies to 7y=7, that is y=1.

Substitute back in the second equation to get x=y+1=1+1=2.