Answer:
7
Step-by-step explanation:
Answer:
Step-by-step explanation:
The table shows a set of x and y values, thus showing a set of points we can use to find the equation.
1) First, find the slope by using two points and substituting their x and y values into the slope formula, 
. I chose (-3, 13) and (0,17), but any two points from the table will work. Use them for the formula like so:
Thus, the slope is 
.
2) Next, identify the y-intercept. The y-intercept is where the line hits the y-axis. All points on the y-axis have a x value of 0. Thus, (0,17) must be the y-intercept of the line.
3) Finally, write an equation in slope-intercept form, or 
format. Substitute the 
and 
for real values.
The represents the slope of the equation, so substitute it for . The represents the y-value of the y-intercept, so substitute it for 17. This will give the following answer and equation:
Answer:
(1) 2π - x² = 0 (2) x = 2.5 cm (3) perimeter = 10 cm
Step-by-step explanation:
(1)The area of the circular coin without the inner square removed is πr² where r = 3 cm is the radius of the coin. So, the area of the coin without the inner square removed is πr² = π(3 cm)² = 9π cm²
The area of the square of x sides removed from its center is x².
The area A of the each face of the coin is thus A = 9π - x²
Since the area of each face of the coin A = 7π cm²,
then
7π = 9π - x²
9π - 7π - x² = 0
2π - x² = 0
(2) Solve the equation 2π - x² = 0
2π - x² = 0
x² = 2π
x = ±√(2π)
x = ± 2.51 cm
Since x cannot be negative, we take the positive answer.
So, x = 2.51 cm
≅ 2.5 cm
(3) Find the perimeter of the square
The perimeter of the square, p is given by p = 4x
p = 4 × 2.51 cm
= 10.04 cm
≅ 10 cm
200x+400y=80
150x+350y=67.5
200x+400y=80
200x=80-400y
x=0.4-2y
150(0.4-2y)+350y=67.5
60-300y+350y=67.5
50y=7.5
y=0.15 or 15 cents per text
200x+400y=80
200x+400(0.15)=80
200x+60=80
200x=20
x=0.1 or 0.10 per minute
So each text costs 5 cents more than each anytime minute
