Mohamed and Li Jing were asked to find an explicit formula for the sequence -5\,,-25\,,-125\,,-625,...−5,−25,−1 25,−625,...Minus, 5, comma, minus, 25, comma, minus, 125, comma, minus, 625, comma, point, point, point. Mohamed said the formula is g(n)=-5\cdot5^{\large{n}}g(n)=−5⋅5 n g, left parenthesis, n, right parenthesis, equals, minus, 5, dot, 5, start superscript, n, end superscript, and Li Jing said the formula is g(n)=-5\cdot5^{\large{n-1}}g(n)=−5⋅ 5 n−1 g, left parenthesis, n, right parenthesis, equals, minus, 5, dot, 5, start superscript, n, minus, 1, end superscript. Which one of them is right?

solution:

→c= a b , that is product of a and b is possible only when when a is m × n matrix and b is n × p matrix.

that is, number of columns of a= number of rows of b.

so, size of matrix , c= a b is , if a = (m × n)matrix

b= (n × p)matrix

then a b = [ (m × n)matrix] ×[   (n × p)matrix ]

→→c= a b= [m × p ] matrix

→→size of product a b will be equal to = number of rows of a × number of columns of b

-3

step-by-step explanation:

a drawing really does here:

so i draw the horizontal line y=2 and the vertical line x=-2 at this intersection i put b (this is where my right angle is going to be).   so point b is at (-2,2).   point a is 5 units long and is also on y=2 so this point has to be (3,2) or (-7,2) -doesn't matter i will go with (3,2).

now we know c is at (-2,y) we don't know the y yet bet we know that c is on x=-2.

we have the area of the triangle is .5bh=12.5

we know the base length is 5 (ab)

we have the height is (2-y) if you look at your

plug in

.5(5)(2-y)=12.5

solve for y to get the y-coordinate for c

2.5(2-y)=12.5

divide both sides by 2.5 giving:

2-y=5

now subtract 2 on both sides

-y=3

y=-3