Find 1+2+3+4+ ... +40, the sum of the first 40 natural numbers.
The sum is

Tell me how you got the it use the figures to answer questions 1and 2. in each diagram, line k is parallel to line l, and line t intersects lines. 1. based on the diagrams, what is the value of x? 2. how would you verify your answer for x?

Using two or more complete sentences, describe how you can find a vector parallel to b=-2,3

Identify which functions are linear or non-linear. a. f(x) = x2 + 1 b. f(x) = 2x + 5 c. f(x) = x 2 + 3 d. f(x) = 3 x + 7 e. f(x) = 4x + 10 2 - 5