No, you cannot used that because you won't be able to solve that.
Answer:
3. a,c
4. a,c
5. c
6. a
7. y=-9x
8. y=x+9
9. y=x-7,y=x+3
13. y=x+5
14. y=8x-2
15. y=5
Step-by-step explanation:
Sry for late response
Answer:
y = (5/4)x + 6
Step-by-step explanation:
The 1st line's equation is:
● 4x + 5y = 20
Substract 4x from both sides
● 4x + 5y - 4x = 20 - 4x
● 5y = 20 -4x
● 5y = -4x + 20
Divide both sides by 5
● 5y/5 = (-4x + 20)/5
● y = (-4/5)x + 4
● y = -0.8x + 4
Let m be the slope of the second line
The lines are perpendicular so the product of their slopes equals -1
Then: m × (-0.8) = -1
● m × (-0.8)= -1
● m = -1/(-0.8)
● m = 1.25
y = 1.25x + b
b is the y-intercept of the line.
To get it replace by the coordinates of a point.
We are given that the line passes through (-4,1)
● y = 1.25x + b
● 1 = 1.25 × (-4) + b
1.25 is 5/5
● 1 = (5/4) × (-4) + b
● 1 = -5 + b
Add 5 to both sides
● 1 + 5 = -5 + b + 5
● b = 6
So the equation is
● y = (5/4)x + 6
