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1 vote
(2x+78)(5x+15) what is x

User Niko Craft
by
4.8k points

2 Answers

8 votes

Answer:

10x^2+420x+1170

Explanation:

(2x+78) (5x+15)

2x (5x+15)+78(5x+15)

10x^2+30x+78(5x+15)

10x^2+30x+390x+1170

10x^2+420x+1170

User Nadavwr
by
5.7k points
5 votes
2x * 5x = 10 ²
2x * 15 = 30x
78 * 5x = 390x
78 * 15 = 1170

10x ² + 30x + 390x + 1170
= 10x ² + 420x + 1170
User Witness
by
5.4k points