So you will need to solve for x and y before evaluating 2x+y....
2x-y=9, y=2x-9 now this will make 4x^2-y^2=171 become:
4x^2-(2x-9)^2=171
4x^2-(4x^2-36x+81)=171
36x-81=171
36x=252
x=7, now we can use 2x-y=9 to solve for y...
2(7)-y=9
14-y=9
-y=-5
y=5
now we know that x=7 and y=5, 2x+y becomes:
2(7)+5
14+5
19
Answer:
10
Step-by-step explanation:
18-8=10
If it takes Tim 2 hours to drive to the campground and it takes 3 times more long then driving to the campground. Then all you have to do is 3 multiplied by 2 and then your answer would be 6 hours.
Hope it helps!
Answer:
simplify -1(3/5)÷(-2/3) = 9/10
=90/100
= .90 and there's your answer
The amount of drinks is a linear function of the number of drinks. The maximum amount that can be purchased is 100 soft drinks.
Let
amount of drinks
number of drinks
For drinks not more than 50

For drinks more than 50.

For a purchase of $85, it means that:

So, we solve for x in both equations.


Collect like terms


Divide through by 0.8

--- approximated


Collect like terms


Divide by 0.7

By comparing both values:



Hence, the maximum amount that can be purchased is 100
Read more about functions at:
brainly.com/question/20286983