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4 years ago

Use substitution to find the solution to the system of equations. 5x+7y=-29 y=x+1

Mathematics

1 answer:

Lostsunrise [7]4 years ago

8 0

Answer:

(x, y) = (- 3, - 2)

Step-by-step explanation:

given the 2 equations

5x + 7y = - 29 → (1)

y = x + 1 → (2)

substitute y = x + 1 into (1)

5x + 7(x + 1) = - 29 ( distribute and simplify left side )

5x + 7x + 7 = - 29

12x + 7 = - 29 ( subtract 7 from both sides )

12x = - 36 ( divide both sides by 12 )

x = - 3

substitute x = - 3 into (2)

y = - 3 + 1 = - 2

solution is (- 3, - 2 )

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3 years ago

Read 2 more answers

Need help please like I think I'm screwed

VLD [36.1K]

1hr 30 mins= 60mins+30mins=90mins
140$=90mins
In one minute, they make 140/90=14/9
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3 years ago

In △ABC, AB = 13, AC = 20, BC = 21. Find the length of the altitude AD

nika2105 [10]

The length of the altitude AD is 12 units.

<h3>How to find the height of a triangle?</h3>

The height of the triangle can be found as follows:

We have to find an angle using cosine law before we can find the height.

Therefore,

20² = 13² + 21² - 2 × 21 × 13 cos B

400 = 169 + 441 - 546 cos B

400 - 610 = - 546 cos B

-210 = - 546 cos B

cos B = -210 / -546

cos B = 0.38461538461

B = cos⁻¹ 0.38461538461

B = 67.3810899783

B = 67.38°

Hence,

sin 67.38° = opposite / hypotenuse

sin 67.38° = AD / 13

cross multiply

AD = 13 sin 67.38°

AD = 11.9999882145

AD = 12 units

learn more on triangle here: brainly.com/question/13387814

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2 years ago

(1) What is the equation, in point-slope form, for a line that goes through (8, −4) and has a slope of negative 5/6 (all fractio

Andreyy89

Formula for point-slope: $y - y1 = m(x-x1)$
Plug in the values (1): $y + 4 = -\frac{5}{6} (x - 8)$ {Choice B}
Plug in the values (2): $y + 6 = \frac{1}{3}(x+ 2)$ {Choice C}
_______________________

[For (3) and (4) we need to solve for slope]

(3)
First, solve for slope.
Formula for slope: $\frac{y2-y1}{x2-x1}$
Plug in values: $\frac{-1-5}{-4-7} = - \frac{6}{11}$
Slope: $- \frac{6}{11}$
Second, we must plug into point-slope form.
Formula for point-slope: $y - y1 = m(x-x1)$
Plug in the values: $y + 1 = - \frac{6}{11}(x + 4)$ {Choice C}

(4)
First, solve for slope.
Formula for slope: $\frac{y2-y1}{x2-x1}$
Plug in values: $\frac{6-(-8)}{-4-7} = - \frac{14}{11}$
Slope: $- \frac{14}{11}$
Second, we must plug into point-slope form.
Formula for point-slope: $y - y1 = m(x-x1)$
Plug in the values: $y - 6 = - \frac{14}{11}(x + 4)$ {Choice D}

8 0

3 years ago

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Find the coordinates of the point on the curve y = 2x² - x - 1 at which the gradient is 7

madreJ [45]

Answer:

See below

Step-by-step explanation:

The derivative of the function is the slope

2x^2 - x -1 take derivative ( f ' )

4x -1 equate to 7

7 = 4x -1

x = 2 sub into the original equation to find y = 5

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2 years ago