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4 years ago

10

The sum of 21 and a number is 30

1 answer:

vagabundo [1.1K]4 years ago

5 0

The answer is 9, because you subtract 21 from 30 and you get 9. When you add 21+9 you get 30.

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What is Satan's last name?

tensa zangetsu [6.8K]

Answer:

Its Lucifer

What kind of question is this

7 0

3 years ago

Evaluate 4(a2 + 2b) - 2b when a = 2 and b = –2

amid [387]

First you simply have to substitute 2 in replace of all the a's, and -2 in replace of all of the b's

4((2)2+2(-2))

Then you want to follow the order of operations, PEMDAS (Parantheses-Exponent-Multiplication-Division-Addition-Subtraction), and multiply within the parantheses.

4(4+(-4))

Next you will add within the parantheses (So add the 4 and -4 together)

4(0)

Lastly multiply

0

Your answer is 0

Hope this helps!

5 0

3 years ago

Read 2 more answers

Help Me | It says: Multiply by the ones. Regroup if needed. Then It says: 2x6 ones = ? Ones or ? Ten and ? Ones | 2x4 tens = ? T

Marianna [84]

2×6 ones= 12 ones
2× 4 tens(40)=80(8 tens)
tens(10)+1 ten=20(2 tens)
2×3 hundreds(300)=600(6 hundreds)

3 0

3 years ago

Read 2 more answers

Given that CD¯¯¯¯¯¯¯¯ is a perpendicular bisector of AB¯¯¯¯¯¯¯¯, where D is on AB¯¯¯¯¯¯¯¯, how can you use the Pythagorean Theor

Liula [17]

Answer:

$(AD)^2 + (CD)^2 = (CA)^2$ and $(CD)^2 + (BD)^2 = (CB)^2$

Step-by-step explanation:

Given

Bisector: CD

of Line AB

Required

Apply Pythagoras Theorem

From the question, CD bisects AB and it bisects it at D.

The relationship between AB and CD is given by the attachment

Considering ACD

From the attachment, we have that:

$Hypothenuse = CA$

$Opposite = CD$

$Adjacent = AD$

By Pythagoras Theorem, we have

$(AD)^2 + (CD)^2 = (CA)^2$

Considering CBD

From the attachment, we have that:

$Hypothenuse = CB$

$Opposite = CD$

$Adjacent = BD$

By Pythagoras Theorem, we have:

$(CD)^2 + (BD)^2 = (CB)^2$

4 0

3 years ago

Read 2 more answers

The length of a rectangle is 1 ft less than twice the width, the area of the rectangle is 21 ft squared. What’s the length

guapka [62]

Answer:

The length of the rectangle is 6 feet

Step-by-step explanation:

Given as :

The length of rectangle is 1 feet less than twice the width

So, let The width of rectangle = w feet

The length of rectangle = ( 2 w - 1 ) feet

The area of the rectangle = 21 feet²

Now,

∵ The area of the rectangle = length × width

Or, 21 feet² = ( 2 w - 1 ) feet × w feet

or, 21 = 2 w² - w

or, 2 w² - w - 21 = 0

or, 2 w² + 6 w - 7 w - 21 = 0

or , 2 w ( w + 3 ) - 7 ( w + 3 ) = 0

or, ( w + 3 ) ( 2 w - 7 ) = 0

So, w = - 3 feet , $\frac{7}{2}$ feet

here we consider only positive value of w i.e $\frac{7}{2}$ feet

∴ The length of rectangle = ( 2 w - 1 ) feet

or, The length of rectangle = 2 × $\frac{7}{2}$ - 1

Or, The length of rectangle = 7 - 1 = 6 feet

Hence The length of the rectangle is 6 feet , Answer

3 0

3 years ago