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Aleksandr [31]
4 years ago
15

A sprinter started his race slowly and then increase his speed by 12.5 miles per hour to reach a top speed of 21 miles per hour

what was the sprinters speed before he increased his speed
Mathematics
1 answer:
IRINA_888 [86]4 years ago
8 0
21 mph - 12.5 mph = 8.5 mph
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Please help!! Show work please!!
Nonamiya [84]

1. 3x - 2y = 8 Subtract 3x on both sides

-2y = 8 - 3x Divide by -2 on both sides to get y by itself

y = -4 + 3/2x


2. a + b / 3 = 5 Multiply 3 on both sides

a + b = 15 Subtract a on both sides to get b by itself

b = 15 - a


3. 12x - 4y = 20 Subtract -12x on both sides

-4y = 20 - 12x Divide -4 on both sides to get y by itself

y = -5 + 3x


4. y + 3 = -5(x - 2) Multiply -5 to (x-2)

y + 3 = -5x + 10 Subtract 3 on both sides to get y by itself

y = -5x + 7

7 0
3 years ago
Read 2 more answers
A monthly contribution of $200 is deposited into an interest-bearing account. If the account has a 4.8% interest rate and compou
Semenov [28]
<span>In 10 years, you will have $31,049.30</span>
7 0
3 years ago
3. The curve C with equation y=f(x) is such that, dy/dx = 3x^2 + 4x +k
Andreas93 [3]

a. Given that y = f(x) and f(0) = -2, by the fundamental theorem of calculus we have

\displaystyle \frac{dy}{dx} = 3x^2 + 4x + k \implies y = f(0) + \int_0^x (3t^2+4t+k) \, dt

Evaluate the integral to solve for y :

\displaystyle y = -2 + \int_0^x (3t^2+4t+k) \, dt

\displaystyle y = -2 + (t^3+2t^2+kt)\bigg|_0^x

\displaystyle y = x^3+2x^2+kx - 2

Use the other known value, f(2) = 18, to solve for k :

18 = 2^3 + 2\times2^2+2k - 2 \implies \boxed{k = 2}

Then the curve C has equation

\boxed{y = x^3 + 2x^2 + 2x - 2}

b. Any tangent to the curve C at a point (a, f(a)) has slope equal to the derivative of y at that point:

\dfrac{dy}{dx}\bigg|_{x=a} = 3a^2 + 4a + 2

The slope of the given tangent line y=x-2 is 1. Solve for a :

3a^2 + 4a + 2 = 1 \implies 3a^2 + 4a + 1 = (3a+1)(a+1)=0 \implies a = -\dfrac13 \text{ or }a = -1

so we know there exists a tangent to C with slope 1. When x = -1/3, we have y = f(-1/3) = -67/27; when x = -1, we have y = f(-1) = -3. This means the tangent line must meet C at either (-1/3, -67/27) or (-1, -3).

Decide which of these points is correct:

x - 2 = x^3 + 2x^2 + 2x - 2 \implies x^3 + 2x^2 + x = x(x+1)^2=0 \implies x=0 \text{ or } x = -1

So, the point of contact between the tangent line and C is (-1, -3).

7 0
2 years ago
Use the law of sines to find m
Rufina [12.5K]

the answer is c. 40.5

5 0
3 years ago
Which algebraic expression is equivalent to the expression below?
Vera_Pavlovna [14]
<h3><u>Answer:</u></h3>

=11n+18

<h3><u>Step-by-step explanation:</u></h3>

3n+13+5+8n

<h3><u>Combine Like Terms:</u></h3>

=3n+13+5+8n

=(3n+8n)+(13+5)

=11n+18

6 0
3 years ago
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