Number 4 is 1
3-x = -x + 3
Answer:
C. 238π cm^3.
Step-by-step explanation:
Surface area = 2 * area of the circular ends + area of the curved length
= 2π r^2 + 2π r* l
= 2 π 7^2 + 2π 7 * 10
= 98π + 140π
= 238π cm^3.
Answer:
x < 3
Step-by-step explanation:
Since 3x - 5 < 4 then we can transpose the inequality to make x the subject of the equation:
If 3x - 5 < 4
⇒ 3x < 4 + 5
⇒ x < 9 ÷ 3
⇒ x < 3
Answer:
x = ± - 3
Explanation:
I'm assuming you want the solutions to that equation, so here goes! (If not, please comment.)
(x-3)(x+9)=27
Let's FOIL this all out and expand. (Remember: First, Outer, Inner, Last.)
x^2 + 9x - 3x - 27
(first+ inner + outer + last)
x^2 + 9x - 3x - 27 = 27
Combine like terms, and add 27 to both sides.
x^2 + 6x - 27 + 27 = 27 + 27
x^2 + 6x = 54
Let's complete the square, because factoring doesn't work, and because it's good practice.
x^2 + 6x + ___ = 54 + ____
In the blank we will put b/2 ^2 = 6/2 ^2 = 3^2 = 9 to complete the square.
x^2 + 6x + 9 = 54 + 9
Now we've got a perfect square factor:
(x + 3)^2 = 63
sqrt(x+3)^2 =
x + 3 = ±
x = ± - 3