One way to write a linear equation is the formula y = mx + b where m is the slope of the function and b is the y-intercept. For this reason, it is known as slope-intercept form.
The slope os calculated via the formula . Lets calculate the slope of the equation first.
So the slope is -0.12. This means for every minute of time used, $0.12 of credit is used. Next, lets plug in the value for m, and the values of an x and y point to find b.
y = 0.12x + b
23.16 = -0.12(57) + b
23.16 = -6.84 + b
30 = b
So, our final equation is y = -0.12x + 30.
Finally, we can use this equation to find the answer to the last part by plugging the value into x.
y = -0.12(60) + 30
y = -7.2 + 30
y = 22.8
So when 60 minutes have been used, there will be $22.80 worth of credit left.
The square root of 81 is 9, this can be proven by squaring 9, which's result is 81.
Answer:
Adding more compound sentences
Step-by-step explanation:
An equation in point-slope form that passes through point P(a,b) is as follows:
y-b=m(x-a) where m=slope, a,b are coordinates of point P.
For a line to pass through P(4,-8)
the equation will look like:
y-(-8) = m(x-4)
simplify left side
y+8=m(x-4)
The given equation has a slope of m=-1/2, so the slope of a line perpendicular to it has a slope of -1/m = -1/(-1/2)=+2
Now go through the answer choices:
a. y+8=2(x-4) => passes through P(4,-8) and has a slope of 2. so TRUE
b. y-4=2(x+8) => has a slope of 2, but passes through (-8,4), which is not P so FALSE
c. y+8=(1/2)(x-4) => passes through P(4,-8), but has the wrong slope (a reflection, not perpendicular) so FALSE
d. y-8=(1/2)(x+4) => passes through a wrong point (-4,8) and has the reflected slope (not perpendicular) so FALSE
Answer:
Step-by-step explanation:
Surely you can figure out how many stairs she has to climb. She has to go down 4, back up to 0, and then up another 4, then back to 0