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2 years ago

Ms. Lynch has 21 coins in nickels and dimes.

Mathematics

1 answer:

bulgar [2K]2 years ago

4 0

Answer:

Step-by-step explanation:So we know x + y = 21 and 5x +10y = 165 We line them up in columns x + y = 21 5x +10y = 165 To eliminate the x variable, I'll multiply every element in the 1st equation by -5. -5x + -5y = -105 5x + 10y = 165 Now we combine (add) the equations, which eliminates x altogether. 5y = 60 ... y = 12 From there, x + 12 = 21 ... x = 21-12 ... x = 9 You should double check. Do 9 nickles and 12 dimes equal $1.65? A very important thing to remember using this method is to do the same thing to each element in the equation that you change! I hope that helps.

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the diameter of a cylindrical construction pipe is 4 ft. if the pipe is 19 ft long, what s it’s volume?

choli [55]

Answer:

76 $\pi$ or 238.76 $units^{3}$

Step-by-step explanation:

The volume of a cylinder is V = $\pi r^{2} h$

Here the radius is r = $\frac{1}{2} d$ = $\frac{1}{2}(4)=2$

The height is given as 19 ft

Then plug in all the numbers into the equation

V = $\pi (2^{2})(19) = 76\pi = 238.76 units^{3}$

3 0

3 years ago

Suppose I have three variables in my dataset called testscr, str, and income. I first execute the command "reg testscr str, r".

IrinaVladis [17]

Answer:

4. It should be less than coefficient on str in the first regression

Step-by-step explanation:

Since the str and income are positively correlated and the coefficient on income in the second regression is positive, the coefficient on str in the second regression therefore should be less than coefficient on str in the first regression.

5 0

3 years ago

I need help on this.

mote1985 [20]

Let's go:

7 = x

38 + x = 180

x = 180 - 38

x = 142°

7 = 142°

I hope I helped you

5 0

3 years ago

What is the opposite integer of 10

NeX [460]

Since 10 is a positive the opposite must be negative. Opposite integer of 10 is -10 ( negative 10).

Happy studying ^-^

4 0

3 years ago

Read 2 more answers

What is the equation, in standard form, of a parabola that contains the following points?

svp [43]

Answer:

Step-by-step explanation:

the the 5 minus the 12 and the 0 minus the negative one all finds it way. back to the equation d

5 0

3 years ago