The figure shows the 50 - foot side of a house and a proposed rectangular garden to be fences in on 3 sides.
The 3 sides, a, b, and x will be made of 40 feet of fencing.
Which of the following is an expression for a in terms of x?
A. 2x+40
B. 2x-40
C. 40-2x
D. 40-x+x
What is the area, in square feet, for the garden if 40 feet of fencing are used and x=15?

Option C 40-2 x

150 square feet

Step-by-step explanation:

Step 1 :

Given that the 3 sides, a,b, and x will be made of 40 feet of fencing,

we have a + b + x = 40

Since this is a rectangular garden , b= x

substituting b= x, we have a + x  + x = 40

=> a+2 x = 40

=> a= 40-2 x

Step 2 :

To find the area in square feet,

when x = 15, a = 40 -  2 * 15 = 40-30 = 10 feet

The length and breadth of the rectangular garden are therefore 5 and 10 feet respectively

Hence, the area of the garden = length  * breadth = 15 * 10 = 150 square feet

f(x) has value 150 at x= 0

and 0 at x= 3

so d(f(x))/dt = slope = -150/3 = -50

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.