The "dot product" of two vectors has several different formulas.
Since you are given the x- and y-coordinates of both vectors a and b, we can apply the formula
a dot b = ax*bx + ay*by, where ax=x-component of vector a, by=y comp of vector b, and so on.
So, for the problem at hand, ax * bx + ay * by becomes
3(-2) + (-8)(-6) = -6 + 48 = 42 (answer). Note that the dot product (or "scalar product" is itself a scalar.
9.4 Ft for the first one
7.5 Ft for the second piece
12 Ft for the Third
he uses 5.2 Ft from the first piece of wood so 9.4 - 5.2= 4.6ft
he uses 6.1 ft from the second piece of wood , 7.5 - 6.1 = 1.4 ft
Nathan didnt use any of the 3rd piece of wood , so he still have 12 Feet of wood remaining so, 12+4.6+1.4 = 18 feet of wood left that he didnt use.
Answer:
4x^2 -5x -2
Step-by-step explanation:
= 5x^2 -3x -7 -x^2 -2x +5
= (5 -1)x^2 +(-3 -2)x +(-7 +5)
= 4x^2 -5x -2