40x+8x^2=0 can be solved for x (there are two solutions):
Divide all 3 terms by the greatest common multiple (which is 8x):
40x+8x^2=0
------------- -----
8x 8x
5 + x = 0 produces the root x = - 5.
Setting 8x = 0 and solving for x produces the root x = 0.
Be certain to check these results. substitute x = -5 into 40x+8x^2=0. Is the resulting equation true or false? Next, subs. x=-5 into 40x+8x^2=0. Is the resulting equation true or false?
The required equation is y = 10000(1.0.25)^2x. The value of Christina’s investment after 20 years is $30,773.14
Compound interest
The interest accrued on a sum of money is known as interest. The formula for calculating the compound interest is expressed as:
y = y0(1+r/n)^nx
where
x is the time taken
r is the rate in decimal
n is the compounding time
Given the following
x = 20 years
n 2(semi annually)
r = 5.7% = 0.057
Substitute
y = 10000(1+0.057/2)^2(20)
y = 10,000(1 + 0.0285)^40
y = 10000(1.0285)^40
y = 30,773.14
Hence the value of Christina’s investment after 20 years is $30,773.14
Learn more on compound interest here: brainly.com/question/24924853
Answer:
x = -5
Step-by-step explanation:
Step 1: Write equation
-2x + 8 = 18
Step 2: Solve for <em>x</em>
- Subtract 8 on both sides: -2x = 10
- Divide both sides by -2: x = -5
Step 3: Check
<em>Plug in x to verify it's a solution.</em>
-2(-5) + 8 = 18
10 + 8 = 18
18 = 18
Answer:
∴ ∑₁⁸i = 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8
Step-by-step explanation:
Given:
To Find:
∑₁⁸i =?
Solution:
Σ This symbol called Sigma means "summation up"
∴ ∑ n mean sum for all n
But if ∑₁³n means Sum for n=1 , 2 ,and 3 ADD
∴ ∑₁³n = 1 + 2 + 3
∴ ∑₁⁸i = 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8
Factors of 4:
<span>1 and 4 </span>
<span>2 and 2 </span>
<span>
</span>