A = L * W
L = 3x + 5
W = x - 2
A = (3x + 5)(x - 2)
A = 3x(x - 2) + 5(x - 2)
A = 3x^2 - 6x + 5x - 10
A = 3x^2 - x - 10 <====
Your answer is two rows of 10 =20
So to start off with this problem, let us call the amount invested in Plan A and B as a and b respectively.
So equation 1: a + b = 250,000
Next, we need to get an equation which is equal to 10,000. So the interest rate in plan a + interest rate in plan b would be equal to 10,000. Rewriting this sentence will give us:
Equation 2: .028a + 0.078b = 10,000
Rewrite the first equation into a = 250,000 - b, and then plug the value into equation 2.
.028(250,000 - b) + 0.078b = 10,000
7,000 - 0.028b + 0.078b = 10,000
-0.028b + 0.078b = 10,000 - 7,000
0.05b = 3,000
b = $60000 amount invested at 2.8% while
250,000 - 60,000 = $190,000 is the amount invested at 7.8%
There u go :) have a great day
Area of the base is 24 in^2
Volume of the triangular pyramid is 80 in ^3
