If the determinant of this matrix is -19, what is the value of a?

a.
3
b.
4
c.
5
d.
6

C)5

Step-by-step explanation:

For a 3x3 matrix

determinent is given by = = a(ei − fh) − b(di − fg) + c(dh − eg)

Given Matrix

determinent of matrix= -6((-3)(-3) − (4)(4)) − 7(a(-3) − (4)(-6)) + 1(a(4) − (-3)(-6))

-19= -6(9-16) - 7(-3a+24) +4a-18

125= 25a

125/25= 25a/25

a= 5 !

step-by-step explanation:

let's assume

number of candles set =x

price of of x candles =p(x)

we are given

a candle maker prices one set of scented candles at $10 and sells an average of 200 sets each week

so, we get point as (200,10)

he finds that when he reduces the price by $1, he then sells 50 more candle sets each week

so, we can find slope

now, we can use point slope form of line

now, we can plug values

we can use point

and find b

now, we can plug it back

and we get

now, we can find revenue

we know that

revenue = price*quantity

so, we get