A1. 12 i.e option D
A2. 3n-7 i.e option A
A3. -6n+20 i.e option D
A4. -70 i.e option C
Step-by-step explanation:
aₙ = a₁ + (n - 1) × d
aₙ = the nᵗʰ term in the sequence
a₁ = the first term in the sequence
d = the common difference between terms
Using the above formula to solve the first part, we have :
For the second part, we have :
For the third part, we have :
For the fourth part, we have :
It's going to be kind of crazy, but you need to use Pythagorean's Theorem for this. That will look like this:

. FOIL out the left side to get

. FOIL out the first of the 2 expressions on the right to get

, and the second of the 2 to get 4x. Our equation now looks like this:

. Combine like terms to get an equation that still has square roots in it that we have to deal with:

and

. We will square both sides to get rid of the square root sign.

. This is a polynomial now that can be factored to solve for x. Bring the 2x over by subtraction and set the polynomial equal to 0.

. Factor out an x, leaving us with x(x-2)=0. That means that x = 0 or x - 2 = 0 and x = 2. Of course if we are solving for the length of a side we know it can't have a side length of 0, so it must have a side length that is a multiple of 2. x = 2
Answer + Step-by-step explanation:


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15⁶ × 15³ = 15⁶⁺³ = 15⁹
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<u>Recall</u> : If a ≠0 ⇒ a⁰ = 1
Then
Since 6⁸ ≠ 0 ⇒ (6⁸)⁰ = 1
2.8392222e+17
Step-by-step explanation:
283838383838382828 + 83838383888282=2.8392222e+17
Answer. First option: t > 6.25
Solution:
Height (in feet): h=-16t^2+729
For which interval of time is h less than 104 feet above the ground?
h < 104
Replacing h for -16t^2+729
-16t^2+729 < 104
Solving for h: Subtracting 729 both sides of the inequality:
-16t^2+729-729 < 104-729
-16t^2 < -625
Multiplying the inequality by -1:
(-1)(-16t^2 < -625)
16t^2 > 625
Dividing both sides of the inequality by 16:
16t^2/16 > 625/16
t^2 > 39.0625
Replacing t^2 by [ Absolute value (t) ]^2:
[ Absolute value (t) ]^2 > 39.0625
Square root both sides of the inequality:
sqrt { [ Absolute value (t) ]^2 } > sqrt (39.0625)
Absolute value (t) > 6.25
t < -6.25 or t > 6.25, but t can not be negative, then the solution is:
t > 6.25