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2 years ago

Solve this quadratic equation by completing the square.

Mathematics

1 answer:

erastova [34]2 years ago

5 0

Answer:

Step-by-step explanation:

x² + 6x = 18

To complete the square, take the coefficient of the x term, halve it, square the result, then add to both sides.

(6/2)² = 3² = 9

x² + 6x + 9 = 18 + 9

(x + 3)² = 27

x + 3 = ±√27

x = -3 ± √27

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High school students from grades 9–10 and 11–12 were asked to choose the kind of band to have play at a school dance: rap, rock,

yanalaym [24]

The correct two-way frequency table for the date will look like this:

RAP ROCK COUNTRY TOTAL
Grades 9-10 40 30 55 125
Grades 11-12 60 25 35 120
TOTAL 100 55 90 245

The sum of the row total is equal to the sum of the column total
125 + 120 = 100 + 55 + 90
245 = 245

8 0

3 years ago

Read 2 more answers

Solve 2x+3y=6 for y Answers listed: y=-2/3x+2 y=2/3x-2 y=2x-3 y=2x+6

iren2701 [21]

2x + 3y = 6 <=>

3y = -2x + 6 <=>

y = -2/3x + 6/3 <=>

y = -2/3x + 2

The answer is the first one.

4 0

3 years ago

Read 2 more answers

1) 5x-2y=4. 2) 3x-5y=13 x-2y=5 3x+y=9

Natali [406]

$\left\{\begin{array}{ccc}5x-2y=4\\3x+y=9&/\cdot2\end{array}\right\\+\left\{\begin{array}{ccc}5x-2y=4\\6x+2y=18\end{array}\right\\----------\\.\ \ \ \ \ 11x=22\ \ \ \ /:11\\.\ \ \ \ \ \ \ x=2\\\\3\cdot2+y=9\\6+y=9\\y=9-6\\y=3\\\\Answer:x=2;\ y=3$

$\left\{\begin{array}{ccc}3x-5y=13\\x-2y=5\end{array}\right\\\left\{\begin{array}{ccc}3x-5y=13\\x=2y+5\end{array}\right\\\\substitute:\\\\3(2y+5)-5y=13\\6y+15-5y=13\\y=13-15\\y=-2\\\\x=2\cdot(-2)+5=-4+5=1\\\\Answer:x=1;\ y=-2.$

5 0

3 years ago

Please help I don’t understand

mihalych1998 [28]

Answer:

the ASA similarity theorem

Step-by-step explanation:

As seen in the picture, the similarities are 2 sides and the angle between them

So the similarity is ASA, second answer choice

3 0

3 years ago

The magnitudes of the moon and sirius are -12.5 and -1.44, respectively. approximately how many times is the moon brighter than

Lelu [443]

Solution:

we are given that

The magnitudes of the moon and Sirius are -12.5 and -1.44 respectively.

we have been asked to find approximately how many times is the moon brighter than Sirius?

The word magnitude is used by the scientist to describe the brightness of moon/star/object etc.

So we can find the brightness by dividing the given values. so we get

$\frac{-12.5}{-1.44} =8.6805$

Hence we can say

The moon is 8.68 times brighter than Sirius.

3 0

3 years ago