Please answer this question​

see explanation

Step-by-step explanation:

(a)

a × - b ( cancel 3 and 15 and 7 and 21 )

= a × - b

= - ab

(b)

3xy(5x²y² - 4yz) ← multiply each term in the parenthesis by 3xy

= 15x³y³ - 12xy²z

answer: 1, 3 and 5 are correct

step-by-step explanation:

for this case we have by definition, if two lines are perpendicular, then the product of their slopes is -1.

then, given the following line:

so,

we are looking for m_ {2}:

then, the line is given by:

we find "b" replacing the given point:

finally, the equation is:

option c