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2 years ago

Evaluate the expression when a= -7 and b=2a-4b

Mathematics

1 answer:

Yanka [14]2 years ago

7 0

a = - 7
b = 2

a - 4b

= (-7) - 4(2)

= - 7 - 8

= - 15.

Hope it helps ya :))

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Stephen record the growth of a plant over 10 weeks for his science project he made a graph that shows how much the plant group e

vazorg [7]

Answer:

y= 6/5x + 2

If you substitute the points (5,8) you get:

8 = 6/5 × 5 + 2

8 = 6 + 2

Step-by-step explanation:

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2 years ago

The edges of the diameter of a circle are at (-1,2) and (3,-1). Write the equation of the circle in general form.

Y_Kistochka [10]

Answer:

(x-1)²+ (y-0.5)²=6.25

Step-by-step explanation:

The standard form of equation of a circle is;

(x-a)²+(y-b)²=r² where (a,b) are the center of the circle and r is the radius

Finding the mid-point of the given points

(-1,2) and (3,-1)⇒midpoint will be 1/2(x₁+x₂) , 1/2(y₁+y₂)

midpoint= {1/2(-1+3), 1/2(2+-1)}

midpoint=(1,0.5)

Finding the radius r; the distance from the center to either of the given two points

Apply the distance formula d=√ (x₂-x₁)² +(y₂-y₁)²

Taking (x₁,y₁) as (1,0.5) and (x₂,y₂) as (-1,2) then

d=√ (-1-1)² +(2-0.5)²

d= √ (-2)²+(1.5)²

d=√4+2.25⇒√6.25⇒2.5

r=2.5

Equation of the circle

(x-1)² + (y-0.5)²=2.5²

(x-1)²+ (y-0.5)²=6.25

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2 years ago

Two opposite sides of a rectangle are each of length x. If the perimeter of the rectangle is 12, then the area, as a function of

Reil [10]

Answer: $x(6-x)$

Step-by-step explanation:

Given : Two opposite sides of a rectangle are each of length x.

Let the other adjacent side be y.

The perimeter of the rectangle is 12 units.

Perimeter of rectangle is given by :-

$P=2(\text{Sum of adjacent sides})\\\\\Rightarrow\ 12=2(x+y)\\\\\Rightarrow\ x+y=\dfrac{12}{2}=6\\\\\Rightarriow\ y=6-x$

The area of rectangle is given by :-

$A=\text{product of two adjacent sides}\\\\\Rightarrow\ A=xy=x(6-x)$

Hence, the area as a function x = $x(6-x)$

7 0

3 years ago

Read 2 more answers

PWEASE HELP ASAP my friends and I cant figure this out I'm hoping one of u guys can

Degger [83]

The number of viruses was 4000 times greater than number of protozoa.

Step-by-step explanation:

Given,

Number of protozoa = $5*10^5$

Number of viruses = $2*10^9$

Let,

x be the number of times number of viruses is greater than number of protozoa.

Number of viruses = Number of time * Number of protozoa

$2*10^9=(5*10^5)x$

Dividing both sides by $5*10^5$

$\frac{2*10^9}{5*10^5}=\frac{(5*10^5)x}{5*10^5}\\\\4*10^3= x\\x=4*10^3 \\x=4000$

The number of viruses was 4000 times greater than number of protozoa.

Keywords: division, scientific notation

Learn more about division at:

#LearnwithBrainly

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3 years ago

Help I need to know plz

lana66690 [7]

Answer:

4 quarts

Step-by-step explanation:

3 gal = 12 quarts

4 pt = 2 quarts

24 cup = 6 quarts

2+6=8 12-8=4

7 0

3 years ago

Evaluate the expression when a= -7 and b=2a-4b​

Evaluate the expression when a= -7 and b=2a-4b