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3 years ago

Y=2x2-4x-5 if x=-2 what is y

Mathematics

1 answer:

kkurt [141]3 years ago

4 0

Answer:

Step-by-step explanation:

y = 2x^2 - 4x - 5.......if x = -2

so sub in -2 for x

y = 2(-2^2) - 4(-2) - 5

= 2(4) + 8 - 5

= 8 + 8 - 5

= 11 <==== y is 11

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The sum of 6 consecutive integers is 339.

Zigmanuir [339]

Answer:

54, 55, 56, 57, 58, and 59 are the numbers

Step-by-step explanation:

Let's pretend that the first number is $n$ .

We know that these numbers are consecutive, meaning each number is one more than the other.

This means that

$n + (n+1)+ (n+2)+ (n+3)+ (n+4)+ (n+5) = 339$ , since each number is consecutive.

We can combine like terms to get $6n + 15 = 339$ .

Now let's solve for n.

$6n + 15 - 15 = 339-15\\\\6n = 324\\\\n = 54$

So $n=54$ . This means the other 5 digits will be one more than the next.

So 54, 55, 56, 57, 58, and 59.

Hope this helped!

4 0

3 years ago

The ratio of boys to girls in Ms.cunninghams class is 2 to 3. There are 18 girls in the class what is the total number in ms.cun

Alenkinab [10]

Answer:the answer is 12

Step-by-step explanation: i just set the ratio and solved for X

6 0

4 years ago

Read 2 more answers

Please help with this too

vovikov84 [41]

Answer:

Step-by-step explanation:

Garden roller is in the shape of cylinder.

So, one revolution = Curved surface area of the cylinder

diameter = 70 cm

radius = 70/2 = 35 cm

h = 100 cm

Curved surface area of the cylinder = 2πrh

= $2*\frac{22}{7}*35*100$

= 22000 square cm

Area covered in 15 revolutions = 15 * 22000

= 330000 square cm

2) Coin

diameter = 22 mm

r = 22/2 = 11 mm

Volume of coin = 66 mm

πr²h = 66

$\frac{22}{7}*11*11*h=66\\\\\\h=\frac{66*7}{11*11*22}\\h=0.17 mm$

8 0

3 years ago

2(a-3)÷(a-4)(a-5)+a-1÷(3-a)(a-4)+a-2÷(5-a)(a-3) simplify.

Arlecino [84]

I'm almost confident that I did this wrong, but i tried...

Answer:

4a-9 ÷ -19

Step-by-step explanation:

(It was easier for me to put it in fractions)

$\frac{2(a-3)}{(a-4)(a-5)}$ + $\frac{a-1}{(3-a)(a-4)}$ + $\frac{a-2}{(5-a)(a-3)}$ (3-a) (a-4) + (5-a) (a-3)

$\frac{2a-6}{(a-4)(a-5)}$ + $\frac{a-1}{(3-a)(a-4)}$ + $\frac{a-2}{(5-a)(a-3)}$ 3 - a · a - 4 + 5 - a · a - 3

$\frac{2a-6}{(2a-20)}$ + $\frac{a-1}{(3-a)(a-4)}$ + $\frac{a-2}{(5-a)(a-3)}$ 3 - a + 1 - a - 3

$\frac{2a-6+a-1+a-2}{(2a-20)+(3-a)(a-4)+(5-a)(a-3)}$ 1 - a - a

$\frac{4a-9}{2a-20+1-2a}$ 1 - 2a

$\frac{4a-9}{2a-19-2a}$

$\frac{4a-9}{-19}$

8 0

3 years ago

I need some help with this as well

Katen [24]

in not sure if it would be correct but i think it would be c because the lines would eventually cross through eachother

Step-by-step explanation:

8 0

2 years ago