Answer:
Step-by-step explanation:
We are given that
Differentiate w.r.t x
By using formula
Hence, the derivative of function
Answers:
- <u>24000 dollars</u> invested at 4%
- <u>18000 dollars</u> was invested at 7%
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Work Shown:
x = amount invested at 4%
If she invests x dollars at 4%, then the rest (42000-x) must be invested at the other rate of 7%
She earns 0.04x dollars from that first account and 0.07(42000-x) dollars from the second account
This means we have
0.04x+0.07(42000-x)
0.04x+0.07*42000-0.07x
0.04x+2940-0.07x
-0.03x+2940
This represents the total amount of money earned after 1 year.
We're told the amount earned in interest is $2220, so we can say,
-0.03x+2940 = 2220
-0.03x = 2220-2940
-0.03x = -720
x = -720/(-0.03)
x = 24000 dollars is the amount invested at 4%
42000-x = 42000-24000 = 18000 dollars was invested at 7%
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As a check, we can see that
18000+24000 = 42000
and also
0.04x = 0.04*24000 = 960 earned from the first account
0.07*18000 = 1260 earned from the second account
1260+960 = 2220 is the total interest earned from both accounts combined
This confirms our answers.
Answer:
x = 4.
Step-by-step explanation:
I am assuming that you want to find the values of x and that WXYZ is a parallelogram.
In a parallelogram opposite sides are equal, therefore:
11x + 1 = 19x - 31
1 + 31 = 19x - 11x
32 = 8x
x = 32/8 = 4.
Answer:
She needs 50 ft² of wood to cover the table
Step-by-step explanation:
You need to know the formula for area of a trapezoid, which is
A = (B1 + B2)h/s (add the bases together, multiply by the height, then divide
by 2)
We are given B1 = 12, B2 = 8, and h = 5, so plug them in and simplify
A = (12 + 8)(5)/2
A = (20)(5)/2
A = 100/2
A = 50 ft²
Answer:
A)$2.50 x b = total cost
B) 9 x 2.50 = $22.5
C) 50 x $2.50 = $125 - $14.75 = $110.25
