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IRINA_888 [86]
3 years ago
14

Solve for x...........................

Mathematics
1 answer:
yaroslaw [1]3 years ago
5 0

Answer:

Option A is correct, i.e. x = -3, x = 7.

Step-by-step explanation:

Given the equation is x² -4x -21 = 0.

We can compare it with general quadratic equation i.e. ax² +bx +c =0.

then a = 1, b = -4, c = -21.

We can use Quadratic formula as follows:-

x = ( -b ± √(b²-4ac) )/2a

x = ( +4 ± √(16-4*1*-21) )/2*1

x = ( +4 ± √(16+84) )/2

x = ( +4 ± √(100) )/2

x = ( +4 ± 10 )/2

x = (4+10)/2 or x = (4-10)/2

x = 14/2 or x = -6/2

x = 7 or x = -3

Hence, option A is correct, i.e. x = -3, x = 7.

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sandra and her friend went to the candy store. each of them purchased a bag of jelly beans. sandra's bag weighed 1.25 pounds. He
Nuetrik [128]

You would subtract.

The question is asking who has more, so to find out, you need to take away the smaller amount from the bigger amount. (1.25-1.05)

So Sandra bought more candy. Hope this helps!



3 0
3 years ago
Read 2 more answers
IN 2013 The number of students in a small school is 284. it is estimated that the student population will increase by 4% every y
Aleks [24]

Answer:

Amount = Initial value × (1 + rate of interest)^years and 374

Step-by-step explanation:

The formula to determine the student population and the estimated student population is given below:

As we know that

Amount = Initial value × (1 + rate of interest)^years

= 284 × (1 + 0.04)^7

= 284 × 1.04^7

= 373.72

= 374

7 0
3 years ago
53 pts!! The function f(x)= 7^x+1 is transformed to function g through a horizontal compression by a factor of 3. What is the eq
e-lub [12.9K]

The value of k will be 3 if the function is transformed by compression factor of 3

Step-by-step explanation:

The horizontal stretch or compression for a function f(x) is given by  g = f(bx) where b is a constant. If b> 0 then the graph of function is compressed.

As it is given in the question that he function is transformed by a compression factor of 3.

Given function

f(x) = 7^x+1\\To\ transform\\g = f(bx)\\g = 7^{3x}+1

The value of k will be 3 if the function is transformed by compression factor of 3

Keywords: Functions, Transformation

Learn more about functions at:

  • brainly.com/question/11280112
  • brainly.com/question/11286417

#LearnwithBrainly

6 0
3 years ago
Read 2 more answers
Please help I think I picked the wrong answer !!
insens350 [35]

Answer:

one solution

Step-by-step explanation:

it has one solution because the slopes of the two equations(1x & 2x) are different, which means the lines of the two equations are not parallel, they have an intersection point(also means one solution).

6 0
3 years ago
Please help as soon as possible <br>Will mark BRAINLIEST ​
zimovet [89]
Answer:
7^2 ( little 2 in the corner)
5 0
3 years ago
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