P=2(l)+2(w)
90=2(4w-5)+2(w)
90= (8w-10)+2w
90=10w-10
10+90=10w-10+10
100=10w
w=10
90=2(4[10]-5)+2(10)
90=2(40-5)+2(10)
90=2(35)+20
90=70+20
90=90
Answer:
Step-by-step explanation:
The value 170 000 is 100x larger than the value 170.
The answer would be C. We know that d is equal to the initial depth of a lake. The two given initial depths are 58 feet and 53 feet, so we know that one of the equations must be either d=58 or d=53. Because there only C has either one of those, d=58, we know that it must be the answer.
To find the other equation, it is just a linear function for the other lake. The y-intercept, or initial value, is 53, so in the equation y=mx+b, it is the b value. The slope, or m value, is 3 feet, so you have y=d=3x+53.
Answer:
4. A
5. B
Step-by-step explanation:
4. I'll solve question four first:
The two marked points on the line are (-2, -3)&(2, 5). Using the formula to find slope(y2-y1/x2-x1), substitute in the points.
5--3/2--2 or 8/4;simplified to 2/1 or 2.
Now use point-slope form: y-y1 = m(x-x1)
y--3 = 2(x--2): Substitute in the values of y1, m, and x1.
y+3 = 2x + 4: Distribute.
y = 2x + 1: Subtract three from both sides.
5. Do the same for question 5.
The first point is (-4, 2), the second point is (4, -1).
-1-2/4--4; -3/8.
Now use point-slope form:
y-2 = -3/8x -12/8: Substitute in the values of x1, y1, m, and distribute the slope to the parentheses.
y = -3/8x + 1/2
