Answer:
x = -1 ± √109
Step-by-step explanation:
2x • 3x + (2 • 3)x + 6x = 648
According to PEMDAS (parentheses/exponents | multiplication/division | addition/subtraction), we should solve the parentheses first.
(2 • 3) = 6
Now we have:
2x • 3x + (6)x + 6x = 648
Now let's multiply.
2x • 3x = 6x²
6 • x = 6x
Now we have.
6x² + 6x + 6x = 648
Combine like terms.
6x² + 12x = 648
Let's factor out a 6.
6(x² + 2x) = 648
Divide both sides by 6.
x² + 2x = 108
Let's use completing the square.
Our equation is in a² + bx = c form.
Divide b by 2.
2/2 = 1
Then square it.
1² = 1
Add 1 to both sides.
x² + 2x + 1 = 108 + 1
Simplify.
x² + 2x + 1 = 109
Now we want to factor the left side. A shortcut is just to use b/2.
(x + 1)² = 109
Take the square root of both sides.
x + 1 = ±√109
The square root is as simplified as possible.
Subtract 1 from both sides.
x = -1 ± √109
Hope this helps!
Answer: Choice D
Explanation:
The increase of 9.8% rounds to 10% when rounding to the nearest ten
An increase of 10% would use the multiplier 1.1
Think of it like saying 1 + 0.10 = 100% + 10%
Similarly, the 5.1% rounds to 5% and an increase of this amount will use the multiplier 1.05
So if we started with 20 items, then 20(1.1)(1.05) is the expression that estimates an increase of 10% followed by an increase of 5%. The order doesn't matter (so you could increase by 5% first, then 10% later).
Answer:
x=0.625
Step-by-step explanation:
-(-2x+1)=9-14x
distribute:
2x-1=9-14x
add 1 to both sides
2x = 10-14x
add 14x to both sides
16x=10
divide by 16 to isolate x
x = 0.625
check:
-(-2(0.625)+1) = 9-14(0.625)
0.25 = 0.25
Answer:
Yes
Step-by-step explanation:
The fraction 4/5 is equivalent to 24/30 (To get this I multiplied both the numerator and denominator by 6). The fraction 5/6 is equivalent to 25/30 (To get this I multiplied both the numerator and denominator by 5).... Since 25 is greater than 24, 25/30 (or originally 5/6) is the larger fraction
Answer:
48.06 to the nearest hundredth.
Step-by-step explanation:
f(x) = -16x^2 + 2x + 48
To find the maximum height we convert to vertex form:
= -16(x^2 + 1/8x) + 48
= -16[x + 1/16)^2 - 1/256] + 48
= -16(x + 1.16)^2 + 16/256 + 48
= 48.0625.
