Question

How many solutions will the following system of linear equations have?

–2x + 4y = –7
y = -1/2x + 5
A.
0
B.
1
C.
2
D.
infinite


For which system of equations is (5, 3) the solution?
A.
3x – 2y = 9
3x + 2y = 14
B.
x – y = –2
4x – 3y = 11
C.
–2x – y = –13
x + 2y = –11
D.
2x – y = 7
2x + 7y = 31


Solve the system of equations.

8x – 3y = 1
–2x + 3y = 11
A.
(–1, –3)
B.
(–1, 3)
C.
(2, 5)
D.
(5, 2)

Answer 1

@Adjax @texaschic101 @anonymous_user

Answer 2

for the 1st question only one solution will be there

Answer 3

2nd question D is the answer
reason substitute the values its simple
or
solve it by normal equations

Answer 4

1. you have to compare the slopes and the y intercepts. In y = mx + b form, the slope is in the m position and the y intercept is in the b position.
-2x + 4y = -7
4y = 2x - 7
y = 1/2x - 7/4
slope = 1/2 and y int = -7/4

y = -1/2x + 5
slope = -1/2 and y int = 5

if slopes and y intercepts are different,which in this problem they are, there is 1 solution.
==========================
sub in (5,3) into the equations to see which comes out true..
D.) 2x - y = 7
2(5) - 3 = 7
10 - 3 = 7
7 = 7 (correct)

2x + 7y = 31
2(5) + 7(3) = 31
10 + 21 = 31
31 = 31 (correct)

answer is D
===========================
8x - 3y = 1
-2x + 3y = 11
--------------add
6x = 12
x = 2

8x - 3y = 1
8(2) - 3y = 1
16 - 3y = 1
-3y = -16 + 1
-3y = -15
y = 5

solution is : (2,5)
====================
any questions ?

Answer 5

thank you