Solve the following system of equations. x + y = 7 & 2x - 3y = -6 ?

Question

a.(-13,20)

b. (2,5)

c. (5,2)

d. (3,4)

Answer 1

x+y=7...............................(1)
2x-3y= -6............................(2)

multipy both sides of (1) by 3 and annd to (2)

3x+3y=21
+
2x - 3y = -6
__________
5x = 15
x = 3

substitute the value of x in (1)
y=4


Thus, your answer is d. (3,4)


TW K

Answer 2

You have to use substitution. If x + y =7, then x =7 -y. So plug 7-y in the next equation for x:
2(7-y) - 3y = -6
14- 2y - 3y = -6
14 - 5y = -6 (subtract 14 from both sides)
-5y = -20 (y=4) Then plug y = 4 into x + y = 7 (x = 3.) The Answer is D.

Answer 3

Try a substitution!

since x+y = 7., then x = 7-y. Substitute this in the other equation, so

2x -3y = -6 becomes
2(7-y) - 3y = -6, solve for y, begin by simplifying

14 - 2y - 3y = -6, or

- 5y = -6 -14, or
- 5y = -20, so y = +4.

Since x = 7- y, we have
x = 7-4 or x=3.

Ans is (d).

Answer 4

I think it is D that is if the first number of the choices is x and the second one is y . hope i helped
1)3+4 +7
2)2 times 3 - 3 times 4= -6

Answer 5

d (3+4=7) and (6-12= -6)

Therefore, x=3 and y=4

Answer 6

(x,y) so you just fill in the numbers to see if it works.

a.) -13 + 20 = 7 Yes 2(-13) - 3(20) = -6 No

b.) 2 + 5 = 7 Yes 2(2) - 3(5) = -6 No

c.) 5 + 2 = 7 Yes 2(5) - 3(2) = -6 No

d.) 3 + 4 = 7 Yes 2(3) - 3(4) = -6 Yes

Answer 7

3x+3y=21
2x-3y= - 6
ADD side by side

5x=15

x=15/5=3
y=4

Answer d . (3,4)

Answer 8

2(x+y=7) or 2x+2y=14
2x-3y=-6 subtract from the first equation
2y-(-3y)=14-(-6)
5y=20
y=4
x=3 or D

Answer 9

d. (3,4)

x + y = 7
2x+2y =14....1st
2x - 3y = -6...2nd
solving both we get
5y = 20
y=4
so x= 3
so (3,4) is the answer.

Answer 10

x+y=7
y=x-7

2x-3y=-6
y=(3y-3)-7
y+7=3y-3
y+10=3y
10=2y
y=5

back to y=x-7

5=x-7

therefore x=2, y=5
The correct answer is B