<span>mostly collect like terms
use associative property which is
(a+b)+c=a+(b+c)
also -a+b-c=(-a)+(b)+(-c) so you can move them around
and remember that:
you just use a general rule
x+x=2x
x^2+x^2=2x^2
3xy4xy=7xy
3x+4x^2=3x+4x^2
you
can only add like terms( like terms are terms that are same name like x
or y are differnt, and like terms have same power exg x^2 and x^3 and
x^1/2 and such
I will oly put the naswers because I don't have much time
first one: 2a+3b+2c
second one: remember that -(-6c)=+6c so the answer is c-10a-2b
third one: -a-8b-5c
</span>
ANSWER:
-78-a
= -78-(-29)
= -78+29
= -49
Well the area of a trapezoid is defined by the following formula:
A =

where b₁ and b₂ are the bases of the trapezoid and h is the height of the trapezoid.
Let's plug in what we know into this formula:
h = 7 the perpendicular distance between the two bases
b₁ = 15 the shorter parallel side
b₂ = 25 the longer parallel side made up of 4 + 15 + 6
so, A =

This is in square units of measure of course, so 140 in²
I’m pretty sure the answer is either D or E but I’m not positive !
Every calculation with multiple operations must abide to BODMAS (Brackets, Other, Divide, Multiple, Addition, Subtraction)
Thus we would multiple first, giving us 86138220. Then we would add giving us: 86145009