What is
1x(3x+4)+5(3x+4)

 " 3x²  + 19x + 20 " .

Step-by-step explanation:

Note:  "ax + bx = (a+b)x " ;

Given:  " 1x(3x + 4) + 5(3x + 4) " ;

Let: "a = 1x " ;  "b = 5 " ; "x" = "(3x +4) " ;

           → 1x(3x + 4) + 5(3x + 4)  =

                 " (1x + 5) (3x + 4) " ;

      Note:  " (a + b)(c + d) = ac + ad + bc + bd " ;

           → (1x + 5) (3x + 4)  = (1x*3x) + (1x* 4) + (5*3x) + (5*4) ;

                                         =  3x²  +   4x   +    15x   + 20 ;

                                              → Combine the "like terms" :

                                                       + 4x + 15x = + 19x ;

                                              →  and rewrite:

                                         =   3x²  + 19x + 20 .

Hope this is helpful!

 Wishing you the best!

last option

step-by-step explanation:

given that δdef is right and isoceles,

assuming that side df is the hypotenuse means that de an ef are the other 2 sides that intersect at 90° and are of equal length.

because they are of equal length, we can say that they are congruent

because they intersect at 90°, their slopes must be opposite reciprocals.

only the last option satisfies these conditions.

answer: sine

step-by-step explanation: