Step-by-step explanation:
A ball is thrown straight up from a rooftop 320 feet high. The formula below describes the ball's height above the ground, h, in feet, t seconds after it was thrown. The ball misses the rooftop on its way down and eventually strikes the ground. How long will it take for the ball to hit the ground? Use this information to provide tick marks with appropriate numbers along the horizontal axis in the figure shown.
h=-16t^2+16t+320
Frank can build a fence in twice the time it would take Sandy. Working together, they can build it in 7 hours. How long will it take each of them to do it alone?
Answer
If Frank and Sandy can build the fence in 7 hours, they must be building
1
7
of the fence every hour.
Now, let the amount of time it takes Sandy be
x
hours so that Frank takes
2
x
hours. Sandy can build
1
x
of the fence every hour and Frank can build
1
2
x
of the fence every hour.
We now have the following equation to solve.
1
x
+
1
2
x
=
1
7
2
+
1
2
x
=
1
7
21
=
2
x
x
=
21
2
=
10.50
Thus, Sandy takes
10.50
hours and Frank takes
21
hours.
Answer:
x= 5/4 ; y= -7/4
Step-by-step explanation:
I will solve your system by substitution.
(You can also solve this system by elimination.)
3x+y=2;5x−y=8
Step: Solve3x+y=2for y:
3x+y+−3x=2+−3x(Add -3x to both sides)
y=−3x+2
Step: Substitute−3x+2foryin5x−y=8:
5x−y=8
5x−(−3x+2)=8
8x−2=8(Simplify both sides of the equation)
8x−2+2=8+2(Add 2 to both sides)
8x=10
8x
8
=
10
8
(Divide both sides by 8)
x=
5
4
Step: Substitute
5
4
forxiny=−3x+2:
y=−3x+2
y=−3(
5
4
)+2
y=
−7
4
(Simplify both sides of the equation)
Answer:
x=
5
4
and y=
−7
4
Given:
side length = 6 ft
To find:
The area of the figure
Solution:
Area of the square = side × side
= 6 × 6
Area of the square = 36 ft²
Diameter of the semi-circle = 6 ft
Radius of the semi-circle = 6 ÷ 2 = 3 ft
Area of the semi-circle = 
Area of the semi-circle = 14.13 ft²
Area of the figure = Area of the square - Area of the semi-circle
= 36 ft² - 14.13 ft²
= 21.87 ft²
Area of the figure = 21.9 ft²
The area of the figure is 21.9 ft².
