Answer:
25/16
Step-by-step explanation:
(4/5)^−2
=
(4/5)^−2
=
(5/4)^2
=
(5/4)*(5/4)
=
5*5/4*4
=
5^2/4^2
=
25/16
(Decimal: 1.5625)
Answer:
D. 0.925x + 0.88y = 0.91(x + y)
Step-by-step explanation:
The important point to remember is that the total mass of pure silver is the same on each side of the equation.
0.925x = mass of pure silver in first alloy
0.88 y = mass of pure silver in second alloy
The final alloy has a mass of (x + y) g and is 91 % pure silver, so
0.925x + 0.88y = 0.91(x + y)
Answer:
Step-by-step explanation:
Let's use a start by using common denominators. 
and 
Now, replace the original equation with the common denominators. 
Solve! 
Answer: 4x^2 -13x + 14
Step-by-step explanation:
(x^2 - 8x + 5)-(-3x^2 + 5x-9)
Subtract -3x^2 from x^2
(4x^2 - 8x + 5)-(5x-9)
Subtract 5x from -8x
(4x^2 -13x + 5)-(-9)
Subtract 9 from 5
4x^2 -13x + 14
