<span>From the problem, you can get this equation:
Jane is 2 years older than Sally
J=z+2
David is 4 times older than Jane.
D=4J
</span>Write two equivalent expressions that represent David’s age in terms of Sally’s age, z, and explain how the two expressions relate to one another.<span>Sally is z years old.
From the 2 equation above, you can get:
</span>D=4J
D=4(z+2)
D=4z+8
D-8=4z
(D-8)/4=z
The two equivalent expression would be D=4z+8 and (D-8)/4=z
The expression that more usefull would be D=4z+8 if you want to determine David age.
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
This is for the first one
Answer:
There would be 144 red cars.
Step-by-step explanation:
3:5 is equal to 3/5
240 * (3/5) = 144
Answer:
45 degrees.
Step-by-step explanation:
When two angles are next to each other along a straight line, their sum = 180 degrees.
180 - 135 = 45