Answer: z=8
Step-by-step explanation:
9z-3z=48
6z=48 ⇔ combine like terms
z=8
Hope this helps
Answer:
c (0,-4)
Step-by-step explanation:
-5x+y = -4
4x - 4y =16
Solve the first equation for y since we are using substitution.
-5x+y = -4
Add 5x to each side
-5x+5x+y = -4+5x
y = 5x-4
Substitute this equation y = 5x-4 into the second equation.
4x -4(5x-4) = 16
Distribute the -4
4x - 4(5x) -4(-4) = 16
4x-20x +16 = 16
Combine like terms
-16x +16 =16
Subtract 16 from each side
-16x+16-16 = 16-16
-16x =0
Divide by -16
x=0
But we still need to find y
y = 5x-4
y = 5(0) -4
y = -4
Answer:
x = 200
Step-by-step explanation:
Given
x - y = 30 ← substitute y = 15 into the equation
x - × 15 = 30 , that is
x - 10 = 30 ( add 10 to both sides )
x = 40 ( multiply both sides by 5 to clear the fraction )
x = 200
Answer:
3 hours walking dogs and 5 hours landscaping
Step-by-step explanation:
<em>Question No 7</em>
Answer:
Please check the explanation.
Step-by-step explanation:
Show that 4x - x² - 7 is always negative.
Given
4x - x² - 7
4x - x² - 7 is always negative because:
- -x²-7 will alwas be negative for all the values of x,
- The value of - x² - 7 will always be less than 4x for all the values of x
Hence, 4x - x² - 7 is always negative
For example,
let suppose we enter x = 1
let suppose we enter x = -1