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crimeas [40]
1 year ago
10

- If 2x2 + 8y = 121.5 and x2 - 8y = 121.5, then x = 9 6.36 16 7

Mathematics
1 answer:
Natalija [7]1 year ago
4 0

Step-by-step explanation:

2x² + 8y = 121.5

x² - 8y = 121.5

Add the equations together to eliminate the y terms.

3x² = 243

x² = 81

x = 9

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Circle 1 has center (−4, −7) and a radius of 12 cm. Circle 2 has center (3, 4) and a radius of 15 cm.
CaHeK987 [17]
<h3>Answer with explanation:</h3>

It is given that:

Circle 1 has center (−4, −7) and a radius of 12 cm.

Circle 2 has center (3, 4) and a radius of 15 cm.

Two circles are said to be similar if by some translation and dilation it could be placed over the other to form the same circle.

The circles are similar because the transformation rule ( x,y ) → (x+7,y+11) can be applied to Circle 1 and then dilate it using a scale factor of 5/4

( Since, as the center of circle 1 is (-4,-7)

so,

(-4+7,-7+11) → (3,4)

( Since, the radius of circle 1 is 12 and that of circle 2 is 15 cm.

so, let the scale factor be k .

that means :

12\times k=15\\\\k=\dfrac{15}{12}\\\\k=\dfrac{5}{4}  )

7 0
1 year ago
Read 2 more answers
Triangle A B C is reflected across line m to form triangle A prime B prime C prime. Triangle A prime B prime C prime is rotated
Helga [31]

Answer:

  1. reflection across line m
  2. rotation about point A'

Step-by-step explanation:

The problem statement tells you exactly what the transformations are.

The first transformation is reflection across line m.

The second transformation is rotation about point A'.

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6 0
1 year ago
The spring has a stiffness k=200n/m and is unstretched when the 25 kg block is at
g100num [7]
To solve this we are going to use the formula fro the force applied to a spring: F=ks
where
k is the spring constant 
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Since we know the F=ma, we can replace that in our formula and solve for a :
ma=ks
a= \frac{ks}{m}
where
a is the acceleration 
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s is the extension 
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We know for our problem that k=200, s=0.4, and m=25. So lets replace those values in our formula to find a:
a= \frac{ks}{m}
a= \frac{(200)(0.4)}{25}
a=3.5 \frac{m}{s^2}

We can conclude that the acceleration of the block when s=0.4m is 3.5 \frac{m}{s^2}.
7 0
1 year ago
240 students to 12 teachers as ratio
grigory [225]

Answer:

1 : 20 20 students for every 1 teacher

Step-by-step explanation:

divide both sides by 12

7 0
1 year ago
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aleksandrvk [35]

Answer:

The alternative hypothesis being tested in this example is that the tire life is of more than 60,000 miles, that is:

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H_0: \mu \leq 60,000

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