How do you evaluate #(5a + 1) ( 3a - 8)#?

Question

2000 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-03-20T09:40:07

#15a^2-37a-8#

#(5a+1)(3a-8)#
#5a(3a-8)+1(3a-8)# [Multiply each term with the other]
#15a^2-40a+3a-8#
#15a^2-37a-8#

Answer 2 · 2018-03-20T09:42:54

Apply FOIL rule (first, outer, inner, last) #(5a+1)(3a-8)=5a*3a+5a*(-8)+3a*1+1*(-8)#
=#15a^2-37a-8#

Apply FOIL rule (first, outer, inner, last)

Try an example with (6+2)(4-2) = 8 x 2 = 16

So we apply foil rule

#6*4+6*(-2)+2*4+2(-2)=24-12+8-4=16#