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3 years ago

Show me how to do this

Mathematics

1 answer:

romanna [79]3 years ago

4 0

Answer:

Step-by-step explanation:

The perimeter of the given triangle:

P = (2x + 1) + (x + 2) + (3x - 9) and P = 36 cm.

Therefore we have the equation:

2x + 1 + x + 2 + 3x - 9 = 36 <em>combine like terms</em>

(2x + x + 3x) + (1 + 2 - 9) = 36

6x - 6 = 36 <em>add 6 to both sides</em>

6x = 42 <em>divide both sides by 6</em>

x = 7

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Solve the inequality <br> 5x+2 < 32

AnnyKZ [126]

Answer:

x<6

Step-by-step explanation:

First, let's work on the left hand side of your inequality, the 5x+2

This means, for instance, to see if it can be simplified at all.

Multiply x and 5

Multiply x and 1

The x just gets copied along.

The answer is x

5*x evaluates to 5x

5*x+2 evaluates to 5x+2

So, all-in-all, the left hand side of your inequality can be written as: 5x+2

Now, let's work on the right hand side of your inequality, the 32

The right hand side of your inequality can be written as: 32

So with these (any) simplifications, the inequality we'll set out to solve is:

5x+2 ‹ 32

Move the 2 to the right hand side by subtracting 2 from both sides, like this:

From the left hand side:

2 - 2 = 0

The answer is 5x

From the right hand side:

32 - 2 = 30

The answer is 30

Now, the inequality reads:

5x ‹ 30

To isolate the x, we have to divide both sides of the inequality by the other "stuff" (variables or coefficients)

around the x on the left side of the inequality.

The last step is to divide both sides of the inequality by 5 like this:

To divide x by 1

The x just gets copied along in the numerator.

The answer is x

5x ÷ 5 = x

30 ÷ 5 = 6

The solution to your inequality is:

x ‹ 6

8 0

3 years ago

Read 2 more answers

Describe the solution to the inequality

Kitty [74]

It’s on open dot because it doesn’t include the 4 and it shades all the numbers greater then 4 (so it goes to the right).

3 0

3 years ago

Twin brothers, Billy and Bobby, can mow their grandparent’s lawn together in 63 minutes. Billy could mow the lawn by himself in

Pepsi [2]

Answer:

<h2>140 minutes</h2>

Step-by-step explanation:

this problem focuses on the combined work rate

both can finish the work under 63 minute

let bobby mow the lawn in x minute

Billy will then mow the lawn in x-25 minutes

Let the completed job = 1 (a mowed lawn)

we can now apply the combined work formula for the two boys as

$\frac{63}{x}+\frac{63}{x-25}=1$

multiplying through by x(x-25 )we have

$63(x-25)+63x= x(x-25)$

open bracket we have

$63x-1575+63x= x^2-25x$

rearranging and collecting like terms we have

$0=x^2-25x-63x-63x+1575 \\\\0=x^2-151x+1575 \\\\x^2-151x+1575=0$

we can now use the quadractic formula

$x=\frac{-b\frac{+}{} \sqrt{b^2-4ac} }{2a}$

a= 1

b= -151

c= 1575

$x=\frac{-(-151)\frac{+}{} \sqrt{151^2-4*1*1575} }{2*1}$

$x=\frac{-(-151)\frac{+}{} \sqrt{22801-6300} }{2} \\\\x=\frac{-(-151)\frac{+}{} \sqrt{16501} }{2} \\\\x=\frac{-(-151)\frac{+}{} 128.45}{2} \\\\$

$x=\frac{-(-151)+128.45}{2} \\\\\x=\frac{279.45}{2} \\\\x=139.72 \\\\\\x=\frac{-(-151)-128.45}{2}\\\\x=\frac{151-128.45}{2}\\\\x=\frac{22.55}{2}\\\\x=11.27$

the first answer x= 139.72 approximately 140 minutes mins is correct for Bobby's time

let us check

$\frac{63}{140}+\frac{63}{140-25}=1\\\\\\0.45+\frac{63}{115} =1\\\\0.45+0.5478=1\\0.997 =1$

we can see that the solution approximates to 1

8 0

4 years ago

Jimmy loaded three bags of sand into his wheelbarrow. The bags weighed 24/12 lbs, 32/35 lbs, and 44/18 lbs. The total amount of

sasho [114]

The correct answer is 5 113/315

3 0

4 years ago

Find QR. <br> A).12<br> B).-8<br> C).9<br> D).6

mihalych1998 [28]

Answer:

D. 6

Step-by-step explanation:

Let's first find x :-

$\sf 3 + 2x + 22 = x + 17$

$\sf 2x + 25 = x + 17$
$\sf 2x - x = 17 - 25$
$\sf x = - 8$

Now that we found x, let's find QR :-

QR = 2x + 22

$\sf QR = 2( - 8) + 22$
$\sf - 16 + 22$
$\sf 6$

Therefore, QR = 6 !!!

4 0

2 years ago

Show me how to do this​

Show me how to do this