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jolli1 [7]
3 years ago
13

Use quadratic formula solve .7x^2 - 28x - 7​

Mathematics
1 answer:
beks73 [17]3 years ago
6 0

Answer:

x = 2 + sqrt(5) or x = 2 - sqrt(5)

Step-by-step explanation using the quadratic formula:

Solve for x over the real numbers:

7 (x^2 - 4 x - 1) = 0

Divide both sides by 7:

x^2 - 4 x - 1 = 0

Add 1 to both sides:

x^2 - 4 x = 1

Add 4 to both sides:

x^2 - 4 x + 4 = 5

Write the left hand side as a square:

(x - 2)^2 = 5

Take the square root of both sides:

x - 2 = sqrt(5) or x - 2 = -sqrt(5)

Add 2 to both sides:

x = 2 + sqrt(5) or x - 2 = -sqrt(5)

Add 2 to both sides:

Answer:  x = 2 + sqrt(5) or x = 2 - sqrt(5)

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2 years ago
What is the value of x
RideAnS [48]

Answer:

x=5

Step-by-step explanation:

We can use the Triangle Angel Bisector Theorem


AB             2x-1

----------= --------------

AC               3x

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Using cross products

3x*9 = 15*(2x-1)

Distribute

27x = 30x-15

Subtract 30x from each side

27x-30x = 30x-30x-15

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4 0
2 years ago
Reflect (10,-8) over the x-axis
cricket20 [7]

Answer:

(10,8)

Step-by-step explanation:

Symmetry over x axis: you keep x, but change the sign of y value.

So, the symmetric of (10,-8) is (10,8)

3 0
3 years ago
Forty-two tickets at $10.50 each cost? _______
Vikki [24]

Answer:

$441

Step-by-step explanation:

Since each ticket costs 10.50 and you buy 42 :

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4 0
2 years ago
Read 2 more answers
Find the area of the triangle. A drawing of a triangle with base of 18 inches and height of 7 inches. The area is square inches.
Citrus2011 [14]

Answer:

63

Step-by-step explanation:

First we multiply :)

18 x 7 = 126

Now we divide :)

126/2 = 63

Therefore your answer will be 63. :)

Have an amazing day!!

Please rate and mark brainliest!!

3 0
2 years ago
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