Answer:
x
=
40
Step-by-step explanation:
Multiply both sides of the second equation by 100 to get rid of the decimals:
0.05<em>n</em> + 0.10<em>d</em> = 1.50
==> 5<em>n</em> + 10<em>d</em> = 150
Multiply both sides of the first equation by -5:
<em>n</em> + <em>d</em> = 21
==> -5<em>n</em> - 5<em>d</em> = -105
Add the two equations together:
(5<em>n</em> + 10<em>d</em>) + (-5<em>n</em> - 5<em>d</em>) = 150 + (-105)
Notice that the terms containing <em>n</em> get eliminated and we can solve for <em>d</em> :
(5<em>n</em> - 5<em>n</em>) + (10<em>d</em> - 5<em>d</em>) = 150 - 105
5<em>d</em> = 45
<em>d</em> = 45/5 = 9
Plug this into either original equation to solve for <em>n</em>. Doing this with the first equation is easiest:
<em>n</em> + 9 = 21
<em>n</em> = 21 - 9 = 12
So Donna used 12 nickels and 9 dimes.
Answer:
156 students
Step-by-step explanation:
To find how many students are in choir this year, multiply 120 by 1.3
120(1.3)
= 156
So, this year, 156 students are taking choir
To finish the table lets see what the differences are between the input (x) and the output (Y)
when input is 32 the output is 20, 32-20 = 12
when input is 14 the output is 2, 14-2 = 12
since the top 2 have the same result, the output is the input minus 12
now that we know that we can finish the table:
when the input is ? the output is -6, so the input = -6 +12 = 6
check: 6-12 = -6 true
when the input is -10, we subtract 12 to get -22 for the output
so the missing input is 6 and the missing output is -22
the function rule would be Y=x-12
