The easiest way is to use (& to memorize) the sum formula for a AP:
Sum = 1st term added to the last term & multiplied by half the number of terms
S = (a+l)n/2
S = (5 + 53)(7/2) = 203
Answer:
x = 2 + sqrt(5) or x = 2 - sqrt(5)
Step-by-step explanation using the quadratic formula:
Solve for x over the real numbers:
7 (x^2 - 4 x - 1) = 0
Divide both sides by 7:
x^2 - 4 x - 1 = 0
Add 1 to both sides:
x^2 - 4 x = 1
Add 4 to both sides:
x^2 - 4 x + 4 = 5
Write the left hand side as a square:
(x - 2)^2 = 5
Take the square root of both sides:
x - 2 = sqrt(5) or x - 2 = -sqrt(5)
Add 2 to both sides:
x = 2 + sqrt(5) or x - 2 = -sqrt(5)
Add 2 to both sides:
Answer: x = 2 + sqrt(5) or x = 2 - sqrt(5)
Answer:
11
220/x=100/5
(220/x)*x=(100/5)*x - we multiply both sides of the equation by x
220=20*x - we divide both sides of the equation by (20) to get x
220/20=x
11=x
x=11.
Answer:
-4f
Step-by-step explanation:
Hi! Let's work on simplifying this.
f(4) = 4f
f(0) = 0, because anything x 0 is 0
f(-8) = -8f
Our equation is 4f + -8f
We can get rid of the plus negative...
4f - 8f
So we get:
-4f
Answer:
2/5 is less than 2/3
2/5 < 2/3
Step-by-step explanation:
2/5 x 3=6/15 is small
2/3x5=1<u>0/15 is big</u>