Answer:
$13,200
Step-by-step explanation:
You need to use the simple interest formula
I = P * r * t
I = Interest accrued
P = Principal amount invested
r = Interest rate you need to divide by 100 to get it in decimal form
t = time, in years if you are given a partial year, divide the months by 12
P = $12,000
r = 7.5% = .075
t = 1
But, because we want I to equal $990 then I is
I = $990
So we ignore our P and instead solve for the P that will give us the desired result.
I = P * r * t
$990 = P * .075 * 1
$990 = P.075 Divide each side by .075
$990/.075 = P.075/.075
$990/.075 = P
$13,200 = P
So, to earn an annual interest income of $990, $13,200 will have to be invested in the 7.5% bond.
Let's solve the equation 2k^2 = 9 + 3k
First, subtract each side by (9+3k) to get 0 on the right side of the equation
2k^2 = 9 + 3k
2k^2 - (9+3k) = 9+3k - (9+3k)
2k^2 - 9 - 3k = 9 + 3k - 9 - 3k
2k^2 - 3k - 9 = 0
As you see, we got a quadratic equation of general form ax^2 + bx + c, in which a = 2, b= -3, and c = -9.
Δ = b^2 - 4ac
Δ = (-3)^2 - 4 (2)(-9)
Δ<u /> = 9 + 72
Δ<u /> = 81
Δ<u />>0 so the equation got 2 real solutions:
k = (-b + √Δ)/2a = (-(-3) + √<u />81) / 2*2 = (3+9)/4 = 12/4 = 3
AND
k = (-b -√Δ)/2a = (-(-3) - √<u />81)/2*2 = (3-9)/4 = -6/4 = -3/2
So the solutions to 2k^2 = 9+3k are k=3 and k=-3/2
A rational number is either an integer number, or a decimal number that got a definitive number of digits after the decimal point.
3 is an integer number, so it's rational.
-3/2 = -1.5, and -1.5 got a definitive number of digit after the decimal point, so it's rational.
So 2k^2 = 9 + 3k have two rational solutions (Option B).
Hope this Helps! :)
The expression of the mathematical statement given as "Jaun's age, x, is 4 times his age 15 years ago" is x = 4 * (x - 15)
<h3>How to rewrite the statement as an expression?</h3>
The mathematical statement is given as
Jaun's age, x, is 4 times his age 15 years ago
From the statement, we have:
x represent Juan's current age
This means that his age 15 years ago is
15 years ago = x - 15
4 times his age 15 years ago is
4 * 15 years ago = 4 * (x - 15)
The above equation is equivalent to his current age
So, we have
x = 4 * (x - 15)
Hence, the expression of the mathematical statement given as "Jaun's age, x, is 4 times his age 15 years ago" is x = 4 * (x - 15)
Read more about expressions at
brainly.com/question/2972832
#SPJ1
The lengths of the rectangles are 7 and 12 respectively. Form the ratio 7/12. The widths of the rects. are x and 5 respectively. Form the ratio x/5. Now equate these two ratios:
7 x
--- = ---
12 5
Solve this for x. One way to do this would be to cross-multiply, obtaining 12x = 35, and solving this result for x. x will be a fraction. Write the numerator and denominator in the boxes given.
Step-by-step explanation: