Answer:
Step-by-step explanation:
7y+5+3y+5=70
10y+10=70
10y=60
y=6
7(6)+5= 42+5= 47
3(6)+5= 18 + 5 =23
47+23= 70
Answer:
-10
Step-by-step explanation:
The constant is the part of the algebraic function or expression that does not change. In this case, as x changes, the constant -10 does not. Thus, -10 is the constant.
Answer:
467,059,500
Thank you for the points! And this is really easy, just add :))
Answer:
7.5 L of 10% solution and 22.5 L of 30% solution
Step-by-step explanation:
Volume of 10% solution plus volume of 30% solution = total volume of 25% volume.
x + y = 30
Acid in 10% solution plus acid in 30% solution = total acid in 25% solution.
0.10 x + 0.30 y = 30 × 0.25
0.10 x + 0.30 y = 7.5
Solve the system of equations, using either substitution or elimination. I'll use substitution:
x = 30 − y
0.10 (30 − y) + 0.30 y = 7.5
3 − 0.10 y + 0.30 y = 7.5
0.20 y = 4.5
y = 22.5
x = 30 − y
x = 7.5
Sarah needs 7.5 L of 10% solution and 22.5 L of 30% solution.
