Answer:
first one is 2.2mm/year and second is 6.2years and -2.2mm/year
Step-by-step explanation:
Just trust me im right
What? I don't understand.
Answer:
20 nickels and 26 dimes
Step-by-step explanation:
- She has $3.60 in nickels and dimes
- a nickel is $0.05 and a dime is $0.10
- let n be the number of nickels and d be the number of dimes
- thus the first equation is 3.6 = 0.05n +0.1d
- If she has 46 coins then n + d = 46
- then n = 46 - d
- sub n = 46 - d into 3.6 = 0.05n +0.1d
- 3.6 = 0.05(46 - d) + 0.1d
- 3.6 = 2.3 -0.05d+0.1d
- 1.3 = 0.05d
- 26 = d
- sub d = 26 into n+d=46
- n+26=46
- n=20
- Check by subbing n=20 and d=26 into 0.05n +0.1d
- 0.05(20) +0.1(26)
- 1+2.6 = 3.6
First we need to make both fractions equal to each other, and that means having to have the denominators the same.
What both 3 and 12 easily go into is 12.
So we need to make both fractions have a denominator of 12, so we multiply.
2/3 * 4/4 = 8 / 12
1/4 * 3/3 = 3 / 12
Now, we know that she has 8 / 12 pounds, and she uses 3 / 12 of it, so now we subtract to find how much she has left.
8 - 3 = 5
Out of the 12 pounds of roast beef, she now has 5 / 12 left.
Answer:
x = 15
Step-by-step explanation:
We want to solve for x in 3*(2x + 5) = 3x + 4x
First simplify.
3*(2x + 5) = 7x
Next, distribute the 3.
3*2x + 3*5 = 7x
6x + 15 = 7x
15 = 7x - 6x
15 = x
