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16 votes
4x2 + 15x + 9 = 0
Solve

2 Answers

9 votes
I solved by factoring
I hope you can see my writing
Nvm I’ll just type it out just incase
4x^2+15x+9=0
(4x^2+3x)+(12x+9)=0
X(4x+3)+3(4x+3)=0
(X+3)(4x+3)=0
X+3=0. 4x+3=0
X=-3. 4x=-3
X=-3/4
X=-3, x=-3/4
Answer in solution set is= {-3, -3/4}
4x2 + 15x + 9 = 0 Solve-example-1
User GowriShankar
by
3.6k points
12 votes

Answer:

x = -3 and x = - 3/4

Explanation:

We can use the quadratic formula to solve for x, considering a = 4 , b = 15, and c = 9:


x=(-b+/- √(b^2-4a*c) )/(2*a) \\x=(-15+/- √((-15)^2-4*4*9) )/(2*4)\\x=(-15+/- √(81) )/(8)\\x=(-15+/- 9 )/(8)=-(6)/(8) \,\,or\,\,-(24)/(8) \\x=-(3)/(4)\,\,or\,\,x=-3

User Seth Warburton
by
3.9k points