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2 years ago

X^(2)+x-20 splitting the middle term

1 answer:

5 0

Are you trying to factorise this?

Here is a way you may not have been taught....
(x + a)(x + b) = x^2 + (a + b)x + ab

So you need to find two factors of -20 that add up to +1
-4 x 5 = -20 and -4 + 5 = 1. Perfect

x^2 + x - 20 = (x - 4)(x + 5)

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What is the slope of the line that passes through the points (-10,8)and (-15,-7)

balandron [24]

Answer:

m = 3

Step-by-step explanation:

Use the slope formula to find the slope m .

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3 years ago

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How many batches of muffins can you make from a 4lb bag of sugar if a batch takes 3/4 cup

slava [35]

Four batches should be the correct answer

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3 years ago

Select the non-linear function from the list of the following:

solong [7]

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2 years ago

The temperature inside a certain industrial machine at time t seconds after startup, for 0 < t < 10, is given by h(t) = 42

frutty [35]

Answer:

$t= \frac{125}{38} s$

Step-by-step explanation:

We are given the temperature inside the machine from startup until 10 seconds later, the formula is:

$h(t)= 42 \cdot t +1 - 4\cdot t +2 (degrees \, C)$

We want to know at what time t the temperature inside the machine will be equal to 128 °C.

So we set:

$h(t)=128$

$42\cdot t+1-4\cdot t+2=128$

Now, we rearrange the equation to keep terms with t on the left hand side and terms without t on the right hand side

$42\cdot t-4\cdot t=128-1-2$

and we simplify:

$(42-4)\cdot t= 128-2-1= 125$

$38 \cdot t = 125$

now it's easy to solve for t:

$t=\frac{125}{38}$

And thus we arrive to the solution.

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2 years ago

Which of the following is the function T(a) if T^-1(a)=11a-2

SpyIntel [72]

Answer:

T(a) =(a+2)/11

Step-by-step explanation:

The inverse of the inverse is the function

To find the inverse let T^-1(a) be y

y = 11a -2

Exchange y and a

a = 11y -2

Solve for y

Add 2 to each side

a+2 = 11y -2 +2

a+2 =11y

Divide each side by 11

(a+2)/11 =y

T(a) =(a+2)/11

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3 years ago