Alang went to the store to buy some walnuts. The price per pound of the walnuts is $7 per pound and he has a coupon for $2.50 off the final amount. With the coupon, how much would Alang have to pay to buy 2 pounds of walnuts? Also, write an expression for the cost to buy pp pounds of walnuts, assuming at least one pound is purchased.

$11.50 is the cost for 2 pounds of walnuts

Expression: 7p - 2.50

Step-by-step explanation:

First, create an expression to represent the cost:

7p will represent the cost, since the walnuts are $7 per pound, and 2.50 needs to be subtracted from this because of the coupon for $2.50 off

So, the expression is 7p - 2.50

Use this expression to find the price for 2 pounds of walnuts:

7p - 2.50

7(2) - 2.50

14 - 2.50

= 11.50

So, the cost with the coupon will be $11.50

answer is 67%

step-by-step explanation:

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12