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Use the quadratic formula to solve this probelm

-3x^2 - 24x -48=0
6x^2 + 5x + 2= 0
4x ^2+8x+3=0

User RealPK
by
8.4k points

1 Answer

1 vote

Answer:

(a)


x=-4

(b)


x=-(5)/(12)+i(√(23))/(12),\:x=-(5)/(12)-i(√(23))/(12)

(c)


x=-(1)/(2),\:x=-(3)/(2)

Explanation:

(a)


-3x^2 - 24x -48=0

we can compare it with standard quadratic equation


ax^2+bx+c=0

we can find a, b and c


a=-3,b=-24,c=-48

now, we can use quadratic formula


x=(-b\pm √(b^2-4ac))/(2a)

we can plug values

and we get


x=(-\left(-24\right)\pm √(\left(-24\right)^2-4\left(-3\right)\left(-48\right)))/(2\left(-3\right))

and we get


x=-4

(b)


6x^2+5x+2=0

we can compare it with standard quadratic equation


ax^2+bx+c=0

we can find a, b and c


a=6,b=5,c=2

now, we can use quadratic formula


x=(-b\pm √(b^2-4ac))/(2a)

we can plug values


x=(-5\pm √(5^2-4\cdot \:6\cdot \:2))/(2\cdot \:6)

we get


x=-(5)/(12)+i(√(23))/(12),\:x=-(5)/(12)-i(√(23))/(12)

(c)


4x^2+8x+3=0

we can compare it with standard quadratic equation


ax^2+bx+c=0

we can find a, b and c


a=4,b=8,c=3

now, we can use quadratic formula


x=(-b\pm √(b^2-4ac))/(2a)

we can plug values


x=(-8\pm √(8^2-4\cdot \:4\cdot \:3))/(2\cdot \:4)

we get


x=-(1)/(2),\:x=-(3)/(2)


User Thejh
by
7.7k points

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