Answer:
Step-by-step explanation:
Let 25% solution is x liters, then 50% solution is (80 - x) liters.
<u>Acid content is going to be same:</u>
- 0.25x + 0.5(80 - x) = 80*0.4
- 0.25x - 0.5x + 40 = 32
- 0.25x = 8
- x = 8/0.25
- x = 32 liters
So 32 liters of 25% solution and 80 - 32 = 48 liters of 50% solution
Answer:
D2=21/24 mile
Step-by-step explanation:
Her it is not specified if it is base or height, it only talks about dimensions, so let's work with dimensions
A=1/12 
D1=4/21mile, D2=?
Area of a triangle 
A=((D1*D2)/2) → 2A=D1*D2 → D2=2A/D1 so D2=(2*1/12)/(4/21) =(1/6)/(4/21) = (1*21)/(6*4)=21/24 mile
Bob charges $140
Andy charges $135
Andy is cheaper
This is the eqn of a str line. <span>y+4=12/7(x-1) would be clearer if written as
</span><span>y+4=(12/7)(x-1). y+4 = (12/7)x - 12/7.
Multiply all terms by 7 to remove the fractions: 7(y+4) = 12x - 12.
Complete the multiplication: 7y + 28 = 12x - 12.
Arrange the x and y terms on the left side and the constants on the right:
-12x + 7y = -40. This is standard form. Some people might disagree and say that -12x + 7y + 40 is standard form. They are equivalent.
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