PLEASE HELP!! I NEED HELP WITH THIS PROBLEM ASAP!! IF YOU HELP I'LL GIVE U BRAINLIEST!

Mathematics

1 answer:

I am Lyosha [343]3 years ago

8 0

Let the amount Tom does = x

Then Larissa’s time would be 3x( 3 times the amount of Tom)

And Neal would also be 3x

The total of the 3 is 84 hours so as an equation you have:

X + 3x + 3x = 84

Combine like terms

7x = 84

Divide both sides by 7

X = 84/7

X = 12 hours

Tom = x, so Tom exercised for 12 hours.

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The value of y is directly proportional to the value of x.If y=12 when x=9, what is the value of x when y=80

Simora [160]

Step 1:

Write the formula connecting y and x.

$\begin{gathered} y\text{ }\propto\text{ x} \\ y\text{ = kx} \\ k\text{ = }\frac{y}{x} \end{gathered}$

Step 2:

Find the value of k when y = 12 and x = 9

$\begin{gathered} k\text{ = }\frac{y}{x}\text{ = }\frac{12}{9}\text{ = }\frac{4}{3} \\ \text{Therefore} \\ y\text{ = }\frac{4}{3}x \end{gathered}$

Step 3

You can find x when y = 80.

$\begin{gathered} \text{Frpm y = }\frac{4}{3} \\ \text{When y = 80} \\ 80\text{ = }\frac{4x}{3} \\ \text{Cross multiply} \\ 4x\text{ = 80}\times3 \\ 4x\text{ = 240 Divide both sides of the equation by 4} \\ x\text{ = }\frac{240}{4} \\ x\text{ = 60} \end{gathered}$

Final answer

x = 60

7 0

1 year ago

Evaluate the integral of arctan(1/x)

fiasKO [112]

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2nd integration:
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