Which equation shows the quadratic formula used correctly to solve 7x2 = 9+ x for x?

Mathematics

2 answers:

SCORPION-xisa [38]3 years ago

7 0

This can also be explained as D on edg :)

____ [38]3 years ago

6 0

Answer:

x = (1 + sqrt(253))/14 or x = (1 - sqrt(253))/14

Step-by-step explanation:

Solve for x:

7 x^2 = x + 9

Subtract x + 9 from both sides:

7 x^2 - x - 9 = 0

x = (1 ± sqrt((-1)^2 - 4×7 (-9)))/(2×7) = (1 ± sqrt(1 + 252))/14 = (1 ± sqrt(253))/14:

Answer: x = (1 + sqrt(253))/14 or x = (1 - sqrt(253))/14

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Three times the sum of a number and 4 is twice a number minus 8.

amm1812

Answer:

Step-by-step explanation:

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3 years ago

A car advertisement claims that a certain car can accelerate from rest to 70 km/hr in 7 seconds find the car acceleration

iVinArrow [24]

Answer:

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3 years ago

Which of the following are solutions to the equation below? check all that apply. 9x^2-6x+1=7

Evgesh-ka [11]

The answer is C and D

First we must make one side of the equation zero, so we subtract 7 on both sides of the equation, making the equation <span>9x^2 - 6x - 6 = 0

Then we will use the quadratic formula to find the answers.

</span>using the Quadratic Formula where:
a = 9, b = -6, and c = -6

and the formula is 6 +- $\sqrt{6^2 - 4(9)(-6)}$ / 2(9)