Answer: " 3x² + 19x + 20 " .
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Step-by-step explanation:
Note: "ax + bx = (a+b)x " ;
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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) " ;
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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 .
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Hope this is helpful!
Wishing you the best!
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