Answer:
(x + 3)(2x + 5)
Step-by-step explanation:
Given
2x² + 6x + 5x + 15 ← grouping the terms
= (2x² + 6x) + (5x + 15) ← factor each group
= 2x(x + 3) + 5(x + 3) ← factor out (x + 3) from each term
= (x + 3)(2x + 5) ← in factored form
9514 1404 393
Answer:
log(128) = t·log(2)
Step-by-step explanation:
You can take logarithms the way the formula is, or you can simplify it first.
<u>As is</u>
log(10000) = log(625) -log(8) +t·log(2)
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<u>Simplified</u>
8·10000/625 = 2^t . . . . . multiply by 8/625
128 = 2^t
log(128) = t·log(2)
_____
Solution:
t = log(128)/log(2) = 7
Answer:
3/4
Step-by-step explanation:
If a number is getting subtracted by a negative number the minus sign and the negative sign cancel eachother and become a positive sign that's why there's 2 plus signs because they became positive
First you open 2 parenthesis with x in each one:
(x )(x )=0
Then, you place the sign of the second term (the x term) in the first parenthesis.
(x+ )(x )=0
Next, you multiply the signs of the x term and the sign of the constant (the third term).
Since + × - = -, then you place a -.
(x+ )(x- )=0
You look at the constant (-18) and the second term (3). What two numbers multiplied give you -18 but subtracted (since the signs inside the parenthesis are opposite) give you 3? Those numbers are 6 and 3.
Since the result of the substraction need to be 3, you place the 6 with the + sign and the 3 with the negative sign (if you think of it, 6-3=3 but 3-6 = -3. That's the reason behind placing the numbers)
(x+6)(x-3)=0
Therefore,
x+6=0 or x-3=0
x=-6 or x=3
Your roots are -6 and 3.
