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3 years ago

Solve. -5x^2+9+7x = 0−5x 2 +9+7x=0

Mathematics

1 answer:

Lynna [10]3 years ago

5 0

Answer:

x = $\frac{-7 \frac{+}{} \sqrt{229} }{-10}$ , or x=2.21327 and -0.81327

Step-by-step explanation:

$-5x^2+7x+9 = 0$

see if equation is factor-able:

$\left[\begin{array}{ccc}?&9\\-5x^2&?\\\end{array}\right]$

the two ? must multiply together to $-45x^2$ and add up to 7x

no two integers times x can solve, so we must use quadratic equation

$x = \frac{-b \frac{+}{} \sqrt{b^2-4ac} }{2a}$ , given a quadratic $ax^2 +bx +c$

$x = \frac{-7 \frac{+}{} \sqrt{49+180} }{-10} = \frac{-7 \frac{+}{} \sqrt{229} }{-10}$

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Answer:

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Step-by-step explanation:

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3 years ago

Evaluate 6+ the sq root of 14+x minus - the sq root of 9x when x=2

romanna [79]

Hello
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3 years ago

A. x-int:-0.5,y-int:1 B. x-int:0.5,y-int:1 C. x-int:-0.5,y-int:-1 D. x-int:1,y-int:0.5

hodyreva [135]

The correct answer is: [D]: " x-int : 1 , y-int: 0.5 " .
_____________________________________________________
Note:
_____________________________________________________
The "x-intercept" refers to the point(s) at which the the graph of a function (which is a "line", in this case) cross(es) the "y-axis".

In other words, what is (are) the point(s) of the graph at which "x = 0" ?

By examining the graph, we see that when " x = 0" ; y is equal to: "1" .

So; the "x-intercept" is at point: "(0, 1)" ; or, we can simply say that the
"x-intercept" is: "1" .
_________________________________________________________ Note:
_____________________________________________________
The "y-intercept" refers to the point(s) at which the the graph of a function (which is a line, in this case) cross(es) the "x-axis".

In other words, what is (are) the point(s) of the graph at which " y = 0 " ?

By examining the graph, we see that when " y = 0 " ; x is equal to: "0.5" .

So; the "x-intercept" is at point: "(0.5, 0)" ; or, we can simply say that the
"y-intercept" is: "0.5 " .
_______________________________________________________
This would correspond to:
_______________________________________________________
Answer choice: [D]: " x-int: 1 , y-int: 0.5 " .
_______________________________________________________
{that is; The "x-intercept" is: "0" ; and the "y-intercept" is: "0.5 ".} .
_______________________________________________________

5 0

3 years ago

In triangle PQR, m∠P = 83°, PQ = 7.6, and PR = 8.6. What is m∠R to the nearest degree? A. 45° B. 55° C. 35° D. 41°

Mila [183]

Answer:

The unknown measurement of angle R to the nearest degree is 41°

Step-by-step explanation:

As you can see, we made a diagram form the given information in the problem. We are trying to find the measurement of angle R which is our unknown angle represented by the question mark.

in order to solve this problem, we are going to be using tangent. Tangent uses the opposite side and the adjacent side from the given or from the unknown angle measurement.

So, our equation will look like this.

$tanx=\frac{7.6}{8.6}$