MyMathLab uiz QUIZ ON 82 83 111213 14 15 1617 18 19 20 This

MyMathLab uiz: QUIZ ON 8.2, 8.3, 111213 14 15 1617 18 19 20 This Question: 1 pt Solve by the elimination method 3x-5y= 57 2x+6y =-18

12)

3x- 5y = 57 (1)

2x+6y = -18 (2)

multiply eq (1) by 2 & eq (2) by 3 ,we get

6x - 10 y = 114

6x+18 y = -54

subtracting eq( 2) from eq (1) ,we get

-28 y = 168

y =-6, putting the value of y = -6 in eq 1 we get x = 9

13) 3 x -y = 6

x = 0,y = -6 , y = 0 , x = 2

(0,-6) & (2,0) are intercepts ,npw you can draw line

14)

the standard form of a line is in the form Ax + By = C where A is a positive integer, and B, and C are integers.

hence b is correct

15) y = (x+3)² -2

y +2 = (x+3)²

hence the vertex is (-3,-2) {(x+3 =0 x = -3 , y+2 = 0 ,y = -2}

16)x + y = 12

y = -x + 12 { this is of form y = mx + c,where m is slope ,c = y-intercept, }

hence slope is -1 ,

y- intercept = c = 12