How can I work out 30% of (blank) is 60?
1 answer:
You might be interested in
Answer:
(- 4, - 12 ) , (4, 12 )
Step-by-step explanation:
Given the 2 equations
y = 3x → (1)
y = x² + 3x - 16 → (2)
Substitute y = x² + 3x - 16 into (1)
x² + 3x - 16 = 3x ( subtract 3x from both sides )
x² - 16 = 0 ( add 16 to both sides )
x² = 16 ( take the square root of both sides )
x = ± = ± 4
Substitute these values into (1) for corresponding values of y
x = - 4 : y = 3 × - 4 = - 12 ⇒ (- 4, - 12 )
x = 4 : y = 3 × 4 = 12 ⇒ (4, 12 )
<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