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2 years ago

Solve quadratic formula x-2x-15=0 the first x is squared

Mathematics

2 answers:

solniwko [45]2 years ago

8 0

$x^2-2x-15=0\\
x^2-5x+3x-15=0\\
x(x-5)+3(x-5)=0\\
(x+3)(x-5)=0\\
x=-3 \vee x=5
$

Oduvanchick [21]2 years ago

6 0

You said that x² - 2x - 15 = 0 .

You could factor the left side:

(x + 3) (x - 5) = 0

This equation is true if either of the factors is zero.

First factor:
x + 3 = 0
x = -3

Second factor:
x - 5 = 0
x = 5

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Answer:

D. Pythagorean

Step-by-step explanation:

Given the identity

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To show that the identity is true, we need to show that the left hand side is equal to right hand side or vice versa.

Starting from the left hand side

cos²x - sin²x ... 1

According to Pythagoras theorem, we know that x²+y² = r² in a right angled triangle. Coverting this to polar form, we have:

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Substituting into the Pythagoras firnuka we have

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5 0

3 years ago

5)Express in standard form: (i)4809000 (ii)0.00849

zysi [14]

Answer:

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1 year ago

Surely help I’ll brainlist. construct a histogram to represent these results.

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Answer:

Step-by-step explanation:

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2 years ago

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Step-by-step explanation:

Considering the left side triangle the blue dotted side is the side "opposite" to the angle given and the side 24 is the side that is "adjacent" to the angle given. The trigonometric ratio tan relates opposite to adjacent. Also, let the blue dotted side be y.

Note: the exact value of tan 60 is $\sqrt{3}$

Thus, we can write $Tan(60)=\frac{y}{24}\\y=24*Tan(60)\\y=24*\sqrt{3} \\y=24\sqrt{3}$

Approximate value (rounded to nearest tenth): $24\sqrt{3} =41.6$

Considering the triangle to the right, the side "opposite" to the angle given (53 degrees) is 41.6 (just found in part (a)) and the side "hypotenuse" (side opposite to 90 degree angle) is x. The trigonometric ratio sine relates opposite and hypotenuse.

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3 years ago

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Step-by-step explanation:

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