Q. Find one value of x that is a solution to the equation:(7x+2)2+6(7x+2)=27x=□
Expand and distribute: Let's first expand the squared term and distribute the 6 in the equation (7x+2)2+6(7x+2)=27.(7x+2)2 becomes (7x+2)(7x+2) which is 49x2+14x+14x+4.6(7x+2) becomes 42x+12. So the equation now is 49x2+14x+14x+4+42x+12=27.
Combine like terms: Combine like terms in the equation. 49x2+14x+14x+42x+4+12=27.This simplifies to 49x2+70x+16=27.
Set equation to zero: Subtract 27 from both sides to set the equation to zero.49x2+70x+16−27=0.This simplifies to 49x2+70x−11=0.
Use quadratic formula: Now we need to solve the quadratic equation49x2+70x−11=0. This does not factor easily, so we will use the quadratic formula, x=2a−b±b2−4ac, where a=49, b=70, and c=−11.
Calculate discriminant: First, calculate the discriminant, which is b2−4ac.The discriminant is 702−4(49)(−11).This is 4900+2156.The discriminant is 7056.
Solve for x: Since the discriminant is positive, we have two real solutions. Now we calculate the solutions using the quadratic formula.x=2⋅49−70±7056.
Calculate square root: Calculate the square root of the discriminant. 7056=84.
Plug square root into formula: Now plug the square root back into the quadratic formula. x=98−70±84.
Simplify solutions: We have two potential solutions for x: x=98−70+84 and x=98−70−84. The first solution simplifies to x=9814, which reduces to x=71. The second solution simplifies to x=98−154, which reduces to x=−4977.
Choose a solution: We have found two values of x that satisfy the equation. We can choose either one as the answer to the question prompt. Let's choose the simpler one, x=71.
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