Answer:
the two number are 7 and 9
Step-by-step explanation:
2*x+y=25
3x-y = 20
add the two equations
2*x+y=25
3x-y = 20
---------------
5x = 45
divide by 5
5x/5 = 45/5
x = 9
lets find y
2x+y = 25
substitute x
2*9 +y =25
18+y =25
subtract 18 from both side
y = 25-18
y =7
Answer:
178
Step-by-step explanation:
Use Pythagorean Theorem to find the Hypotenuse
30^2+72^2=78^2
Use perimeter formula
a+b+c
38+72+30
Answer:The answer is B !
Step-by-step explanation:
Let x be the number of people that can be seated.
The value of x is some number 0 or greater, such that this number is a whole number (we can't have half a person). This means that

which is the same as saying

The instructions state that we can seat up to 1200 people. This is the max capacity. We can't go over this amount. So we will also have
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indicating that x can be less than 1200 or equal to 1200.
So putting the two inequalities together, we get
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Note: if you haven't learned about compound inequalities yet, then the teacher may only want
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as the answer.
Answer:
468.4 meters
Step-by-step explanation:
Find the width of the rectangle.
The area of a rectangle is A=length*width. Substitute the values of length and area and solve for width.
A=length*width
8,400=140*width
60= width
Use the width of the rectangle to find the circumference of the semicircles. Since each semicircle is half of a circle, the perimeter of the two semicircles is equal to the circumference of one circle.
The circumference of a circle is equal to pid, where d is the diameter. The diameter of the semicircle is the same as the width of the rectangle.
So, the diameter is 60 meters. Substitute the diameter into the formula for the circumference and simplify using 3.14 for pi.
≈188.4
(2 times 140)+ 188.4
So, the perimeter of the track is 468.4 meters.