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2 years ago

7

Blake ran three miles for his workout today. He ran the first mile in 7.2 minutes, the second mile in 7.35 minutes, and the thir

d mile in 7.5 minutes. What was his total time for the three miles?
8.82 minutes

22.05 minutes

21.15 minutes

21.05 minutes

2 answers:

NeTakaya2 years ago

6 0

Answer:

22.05 minutes

Step-by-step explanation:

7.2 + 7.35 + 7.5 = 22.05 minutes

Cerrena [4.2K]2 years ago

3 0

22.05 minutes

7 + 7 + 7 = 21
.2 can be rounded to .20 and .5 to .50
.20 + .35 + .50 = 1.05
21 + 1.05 = 22.05

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3 years ago

A first number plus twice a second number is 14. twice the first number plus the second totals 31. find the numbers.

topjm [15]

------------------------------------------------------------
Define the two numbers
-----------------------------------------------------------
Let the first number be x.
Let the second number be y.

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Form equations and solve x and y
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x + 2y = 14 ------------------ (1)
2x + y = 31 ------------------ (2)

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Equation (1) x 2
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Equation (1a) - 2
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3 years ago

Find parametric equations for the tangent line to the curve with the given parametric equations at the specified point. Illustra

Rainbow [258]

Answer:

$x = t$

$y = 1 - t$

$z = 2t$

Step-by-step explanation:

Given

$x=t$

$y=e^{-t}$

$z=2t-t^2$

(0, 1, 0)

The vector equation is given as:

$r(t) = (x,y,z)$

Substitute values for x, y and z

$r(t) = (t,\ e^{-t},\ 2t - t^2)$

Differentiate:

$r'(t) = (1,\ -e^{-t},\ 2 - 2t)$

The parametric value that corresponds to (0, 1, 0) is:

$t = 0$

Substitute 0 for t in r'(t)

$r'(t) = (1,\ -e^{-t},\ 2 - 2t)$

$r'(0) = (1,\ -e^{-0},\ 2 - 2*0)$

$r'(0) = (1,\ -1,\ 2 - 0)$

$r'(0) = (1,\ -1,\ 2)$

The tangent line passes through (0, 1, 0) and the tangent line is parallel to r'(0)

It should be noted that:

The equation of a line through position vector a and parallel to vector v is given as:

$r(t) = a + tv$

Such that:

$a = (0,1,0)$ and $v = r'(0) = (1,-1,2)$

The equation becomes:

$r(t) = (0,1,0) + t(1,-1,2)$

$r(t) = (0,1,0) + (t,-t,2t)$

$r(t) = (0+t,1-t,0+2t)$

$r(t) = (t,1-t,2t)$

By comparison:

$r(t) = (x,y,z)$ and $r(t) = (t,1-t,2t)$

The parametric equations for the tangent line are:

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2 years ago

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Answer:shirt = $22.5

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Using elimination method

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3 years ago