Answer:
you need to explain what the question is
Step-by-step explanation:
Step-by-step explanation:
(-6x +3y=9 )×4
( 10x+4y)×3
-24x +12y =36
30x+12y= -18
-24x+12y- (30x+12y)= 36-(-18)
-54x = 54
x= -1
by using 10x +4y = -6
apply x= -1
-10+4y= -6
4y= -6 +10
4y=4
y=1
so the answer is x=-1 and y= 1
C = 15x + 50
let c be $125 since c represents the cost
15x + 50 = 125
15x = 125 - 50
15x = $75
x = 75 ÷ 15
x = 5
Answer:
0.06 liters
Step-by-step explanation:
acid concentration of 65% means that it of 100 units of that solution 65 are acid, and the remaining 35 are water.
so, 100 units are 0.2 liters in this example.
that means that 65/100 × 0.2 = 0.13 liters are acid.
35/100 × 0.2 = 0.07 liters are water
we get a 50% concentration, when we have the same amount of water and acid in the solution (acid is only half of 50% of the solution).
the account of acid remains the same, as we are only adding water.
so, how much water do we need to get from 0.07 liters to 0.13 liters (the same as the already present acid) ?
0.13 - 0.07 = 0.06 liters
50 * 3 = 150 and 150 * 3 = 450
So the answer is b 150