With y-x=0, add x to both sides to get y=x.
Now you can substitute either x or y
7x-9x=8 or 7y-9y=8 which is the same thing
-2x=8 or -2y=8
x=-4 or y=-4
Hope this helped!
Answer:
Step-by-step explanation:
yes
Answer:
14/5
Step-by-step explanation:
That " • " signifies multiplication.
g(x) = (x + 1) / (x - 2) and h(x) = 4 - x are to be multiplied together to obtain (g·h)(x):
(x + 1)(4 - x)
(g·h)(x) = --------------------
x - 2
This could be simplified.
But our task is to evaluate this product function at x = -3. So we replace each instance of x with -3:
( -3 + 1 )( 4 - [-3] ) (-2)(7)
(g·h)(-3) = -------------------------- = ----------- = 14/5
-3 - 2 -5
Answer:
12 mph & 4 mph
Step-by-step explanation:
Let s and s - 8 be the speed of Caitlin going on her friend and her speed on her way home respectively.
Distance = Speed × Time
Distance/Speed = Time
9/s + 9/(s - 8) = 3
9(s - 8) + 9s = 3s(s - 8)
9s - 72 + 9s = 3s² - 24s
3s² - 42s + 72 = 0
s² - 14s + 24 = 0
(s - 2)(s - 12) = 0
s - 2 = 0
s = 2
s - 12 = 0
s = 12
If s = 2, then s - 8 = - 6 < 0. We want s and s - 8 to be positive so s = 12 mph. It follows that her speed on her way home is 4 mph.