9514 1404 393
Answer:
(x, y) = (3, 12)
Step-by-step explanation:
Using the given variable definitions, we can write the equations ...
y = x + 9
2(x +y) = 30
__
Solving the second equation for y, we have ...
y = 15 -x
Substituting this into the first equation gives ...
15 -x = x +9
6 = 2x . . . . . . . . . add x-9
3 = x . . . . . . . . . . divide by 2
y = 3+9 = 12 . . . . substitute into the first equation
The numbers are (x, y) = (3, 12).
2 times a number minus 9 is less than or equal to 21. and in inequality form that’s: 2x - 9 >_ 21 and u make a number line and a closed circle on 15 and an arrow going right. i hope i understood your question right
Answer:
61.25%
Step-by-step explanation:
How many ml of 20 percent acid should be added to pure acid
to make 70 ml of 30 percent acid?
:
let x = amt of 20% mixture
then
(70-x) = amt of pure acid
:
0.20x + (70-x) =0 .30(70)
0.20x + 70 - x = 21
= 21 - 70
-0.8x =-49
x = 61.25%
x = +61.25 ml of 20% stuff
Answer:
15 pieces
Step-by-step explanation:
a ratio of 1:3 has 4 total parts, meaning that each part is 5.
20/3 = 15 so that means he has 5 pieces of chocolate and 15 of hard candy.
