Answer:
-7
Step-by-step explanation:
21 ÷ (4+3) - 10
=> 21 ÷ (7) - 10
=> 3 - 10
=> -7
Answer:
150 mL
Step-by-step explanation:
We need a mixture that is at 50%, now we have 200 mL at 35% and another mixture that is at 70%, that is, we must calculate how much of this mixture is added, by the following equation
200 * 35% + x * 70% = 50% (x + 200)
70 + 0.7 * x = 0.5 * x + 100
0.7 * x - 0.5 * x = 100 - 70
0.2 * x = 30
x = 30 / 0.2
x = 150
150 mL must be added so that the mixture is 50%.
Answer:
No you wouldn't because you are not dividing or multiplying by a negative number.
Step-by-step explanation:
Answer:
HI
Step-by-step explanation:
First of all, x>y
x-y=40
and
x+y=66
add them equations together to eliminate
x-y=40
<u>x+y=66 +</u>
2x+0y=106
2x=106
divide by 2
x=53
sub back
x-y=40
53-y=40
minus 53 both sides
-y=-13
y=13
the numbers are 53 and 13