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3 years ago

Complete the square on the following quadratic x^2+18x+7=0 what value is added to both sides of the equation.

1 answer:

7 0

X^2 + 18x + 7 = 0
x^2 + 18x = -7
x^2 + 18x + 81 = -7 + 81....add 81 to both sides
(x + 9)^2 = 74
x + 9 = sqrt 74
x = -9 (+-) sqrt 74

x = -9 + sqrt 74
x = -9 - sqrt 74

the reason u add 81 to both sides.....u take half of the x term, then square it.
half of 18 is 9....9^2 = 81

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Josie is making pizza dough. Complete the double number line by filling in the missing values

Softa [21]

Answer:

$n = \frac{4}{3}c$

$c:0\ \ \ \frac{3}{4}\ \ \ \frac{3}{2}\ \ \ \frac{9}{4}\ \ \ 3\ \ \ 3\frac{3}{4}\\n:0\ \ \ \ 1\ \ \ 2\ \ \ 3\ \ \ \ 4\ \ \ \ 5$

Step-by-step explanation:

Given

See attachment for complete question

Required

Complete the double number line

The given double number lines represent a linear function between cups of flour (c) and number of batched (n)

Pick any two pairs:

$(c_1,n_1) = (\frac{3}{4},1)$

$(c_2,n_2) = (3\frac{3}{4},5)$

First, calculate the rate of change (i.e. slope, m):

$m = \frac{n_2 - n_1}{c_2 - c_1}$

$m = \frac{5-1}{3\frac{3}{4} - \frac{3}{4}}$

$m = \frac{4}{3}$

So: the equation is:

$n = m(c - c_1) + n_1$

This gives:

$n = \frac{4}{3}(c - \frac{3}{4}) + 1$

$n = \frac{4}{3}c - 1 + 1$

$n = \frac{4}{3}c$

So, the above represents the relationship between n and c.

<u>To complete the table</u>

When $n = 2$

Substitute $n = 2$ in: $n = \frac{4}{3}c$

$2 = \frac{4}{3}c$

Make c the subject

$c = \frac{3*2}{4}$

$c = \frac{3}{2}$

When $n = 3$

Substitute $n = 3$ in: $n = \frac{4}{3}c$

$3 = \frac{4}{3} * c$

Make c the subject

$c = \frac{3*3}{4}$

$c = \frac{9}{4}$

When $c=3$

Substitute $c=3$ in: $n = \frac{4}{3}c$

$n = \frac{4}{3} * 3$

$n = 4$

So, the complete table is:

$c:0\ \ \ \frac{3}{4}\ \ \ \frac{3}{2}\ \ \ \frac{9}{4}\ \ \ 3\ \ \ 3\frac{3}{4}\\n:0\ \ \ \ 1\ \ \ 2\ \ \ 3\ \ \ \ 4\ \ \ \ 5$

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2 years ago

For the direct variation such that when y = 2 then x = 3 , find the constant of variation ( k) and then find the value of y when

Sergeu [11.5K]

Answer:

k is 2/3 and y is -1/3 when x is -0.5.

Step-by-step explanation:

The direct variation relationship is y = kx, where k is the const. of var.

Subbing 3 for x and 2 for y, 2 = 3k, or k = 2/3.

Now, if x = -0.5, y = (2/3)(-1/2) = -1/3

k is 2/3 and y is -1/3 when x is -0.5.

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Convert the volume from L to mL according to capacity of the can.

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