Question

Select the coordinate point that is a solution of equations. 2x+y=7; 3x-4y=5

Answer 1

Answer:

D(3,1)

Step-by-step explanation:

The given equations are:

$2x+y=7...(1)$

and

$3x-4y=5...(2)$

Multiply equation (1) by 4.

$\Rightarrow 8x+4y=28...(3)$

Add equation (2) and (3)

$\Rightarrow 11x=33$

Divide through by 11.

$\Rightarrow x=3$

Put x=3 into equation (1)

$2(3)+y=7$

$6+y=7$

$y=7-6$

$y=1$

The solution is (3,1)

The correct choice is D

Answer 2

Answer:

D (3,1)

Step-by-step explanation:

solving simultaneous equations

Arrange equations

2x+y=7

3x-4y=5

make y side cancell by addition by multiplying by 4 and 1 as shown

4{2x+y=7}

1{3x-4y=5}

8x+4y=28

3x-4y=5

11x=33

x=33/11=3

substitute for x=3 in 3x-4y=5

9-4y=5

4=4y

y=1