$79 cell phone ; 20% discount

63.2

Step-by-step explanation:

To get the amount of the cell phone after the discount, you can do that by 2 really easy ways. First, convert 20% into a decimal or fraction. It's 0.2 or 20/100 sice it's 20% and percentages are out of 100. Now, you can multiply 0.2 by 79. But, there is a much easier way. When you have a discount of 20% off, then this means that the price after will have 80% of the price before. So, you can just find 80% of 79 and this way you will NOT have to subtact the    20% from the initial cost.

f(x) = - 2/3x + 5; f(5/2)

substitute 5/2 in for x:

f(5/2) = -2/3(5/2) + 5

simplify the right side:

f(5/2) = -5/3 + 5

f(5/2) = 10/3

answer:

f(5/2) = 10/3

i hope this you!

step-by-step explanation:

i found the koficent of the linear function and i foun c acordind to the strict formula y=kx+c and then i took 2 as an x and replacet it on the formula i found and then foun the y