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3 years ago

-8x + 7y=-16 4x + y=-28

Mathematics

1 answer:

topjm [15]3 years ago

5 0

Answer:

x=-5

y=-8

Step-by-step explanation:

let first equation be equation 1

let second equation be equation 2

so we gather the like terms

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Suppose you have 100 ft of string to rope off a rectangular section for a bake sale at a school Fair. The function A=x^2+50x giv

cupoosta [38]

Answer:

Therefore the width is 25 feet for getting maximum area.

The maximum area of the rectangle is 625 square feet.

Therefore the range is 0≤A≤625.

Step-by-step explanation:

Given function is

A = - x²+50x

We know that ,

If y = ax²+bx+c

For the maximum $x=-\frac{b}{2a}$

Here a = -1 , b= 50 and c=0

Therefore the width $x= -\frac{50}{2.(-1)} = 25$

Therefore the width is 25 feet for getting maximum area.

The maximum area =[ -(25)²+50.25] square feet

= 625 square feet

The area can not be negative and maximum area is 625 square feet.

Therefore the range is 0≤A≤625.

5 0

3 years ago

The life expectancy of a circulating coin is 30 years. The life expectancy of a circulating dollar bill is only

Afina-wow [57]

Life expectancy of dollar bill = d
life expectancy of coin = c

d = 1/20 c

substitute value in for c (30)

d = 1/20 * 30
d = 30/20
d = 1.5

life expectancy of a dollar bill = 1.5 years

3 0

3 years ago

a running relay team ran a 400 meter race in a record-setting time of 36 seconds.what was their average speed to the nearest ten

s344n2d4d5 [400]

Answer:

406858reuyy igcbjiy469633

7 0

2 years ago

A ball is dropped from a height of 12 feet and returns to a height that is one-half of the height from which it fell. The ball c

juin [17]

1 st hit=12 ft
2nd hit=2*6=12 ft
3rd hit=2*3=6 ft
4th hit=2*1.5=3 ft
total distance=12+12+6+3=33 ft

4 0

2 years ago

Read 2 more answers

The height of a triangle is 8ft greater than the base. The area of the triangle is 136.5 square ft. Find the length of the base

mixer [17]

Answer:

the base is 9/2 ft and the height is 9/2 + 8, or 25/8, ft.

Step-by-step explanation:

Note that the formula for the area of a triangle is A = (1/2)(base)(height). Let's abbreviate that to A = (1/2)(b)(h). We are told that h = b + 8.

Then A = 136.5 = (1/2)(b)(b + 8), or

(after multiplying both sides by 2)

A = 273 = b^2 + 8b

which, when put into standard quadratic form, becomes:

b^2 + 8b - 273 = 0

The coefficients of this quadratic are a = 1, b = 8 and c = -273.

Thus, the discriminant is b^2 - 4ac, or 64 - 4(1)(-273) = 1156 = 17^2.

The roots are then

-8 ± √1156 -8 ± 17

x = -------------------- = ------------ = 9/2 and -25/2

2 2

Only the root 9/2 makes sense here, because measurements of length are positive.

Thus, the base is 9/2 ft and the height is 9/2 + 8, or 25/8, ft.

3 0

3 years ago