Answer:
6 mg of the metal needs to be added.
Step-by-step explanation:
Let the amount (in mg) of metal that needs to be added by y.
Therefore, the amount of silver in the above metal is 0.04y.
Prior to mixing, 11 mg of a metal contained 38% of silver (Given).
Therefore, the amount of silver before= 
= 4.18 mg
The total amount of silver after mixing, 4.18 + 0.04y mg
The total amount of metal after mixing, 11 + y mg
New percentage of silver = 26% .
Thus, 
y=6 mg
Therefore, the amount of metal that needs to be added is 6 mg.
Answer:
30x^4−12x^3=6x^3(5x−2) = True
4x^2+10x=2x(2x+5) = True
100x^3+5=5x^3(20x+1) = False
8x^3−6x=2x^3(4−3x3) = False
Step-by-step explanation:
Answer:
3) x = 15; 95 and 85 4) x = 12; 98 for both angles
Step-by-step explanation:
2x + 65 + 3x + 40 = 180 Set the equations equal to 180
5x + 105 = 180 Combine like terms
- 105 - 105 Subtract 105 from both sides
5x = 75 Divide both sides by 5
x = 15
Plug 15 into both equations
2(15) + 65 = 95
3(15) + 40 = 85
4) 5x + 38 = 9x - 10 Set the equations equal to each other
- 5x - 5x Subtract 5x from both sides
38 = 4x - 10
+ 10 + 10 Add 10 to both sides
48 = 4x Divide both sides by 4
12 = x
Plug 12 into both equations
5(12) + 38 = 98
9(12) - 10 = 98
Answer:
A = 5x² + 6x + 1
Step-by-step explanation:
The area (A) of a trapezoid is calculated as
A = 
h (a + b)
where h is the height and a, b the parallel bases, thus
A = (x + 1)(6x - 5 + 4x + 7)
= (10x + 2)(x + 1)
= (5x + 1)(x + 1) ← distribute using FOIL
= 5x² + 6x + 1
Four hundred three and six hundred and 8
