Question

plzz help me ....solving the equation.....I'll follow the one who gives the answer at first...​

Answer 1

$\fbox{Solution\:of\:18}$

$\sqrt{3x + 4} = x \\ = > \frac{1}{2} (3x + 4) = x \\ = > 3x \times \frac{1}{2} + 4 \times \frac{1}{2} = x \\ = > \frac{3x}{2} + 2 = x \\ = > \frac{3x + 4}{2} = x \\ = > 3x + 4 = 2x \\ = > 4 = 2x - 3x \\ = > - x = 4 \\ = > x = - 4$

$\fbox{Solution\:of\:19}$

$5(3x + 1)^{2} + 6(3x + 1) - 8 = 0 \\ = > {5y}^{2} + 6y - 8 = 0 \\ = > {5y}^{2} + (10 - 4)y - 8 = 0 \\ = > ( {5y}^{2} + 10y) - (4y - 8) = 0 \\ = > 5y(y + 2) - 4(y + 2) = 0 \\ = > (5y - 4)(y + 2) = 0 \\ here \: we \: get \: two \: values \: of \: y\\ (5y - 4) = 0 \\ = > 5y = 4 \\ = > y = \frac{4}{5} \: and \\ (y + 2) = 0 \\ = > y = - 2 \\ as \: we \:know \: - ve \: is \: neglisible \: so \: \\ the \: value \: y \: is \: \frac{4}{5}$

According to the question we have to find the value of x, so

$y = \frac{4}{5} \\ = > 3x + 2 = \frac{4}{5} \\ = > 3x = \frac{4}{5} - 2 \\ = > 3x = \frac{4 - 10}{5} \\ = > 3x = \frac{ - 6}{5} \\ = > x = \frac{ - 6}{ \frac{5}{3} } \\ = > x = \frac{ - 6}{5 \times 3} \\ = > x = \frac{ - 6}{15} \\ = > x = \frac{ - 2}{ 5}$

Answer 2

$\fbox{Solution\:of\:18}$

$\sqrt{3x + 4} = x \\ = > \frac{1}{2} (3x + 4) = x \\ = > 3x \times \frac{1}{2} + 4 \times \frac{1}{2} = x \\ = > \frac{3x}{2} + 2 = x \\ = > \frac{3x + 4}{2} = x \\ = > 3x + 4 = 2x \\ = > 4 = 2x - 3x \\ = > - x = 4 \\ = > x = - 4$

$\fbox{Solution\:of\:19}$

$5(3x + 1)^{2} + 6(3x + 1) - 8 = 0 \\ = > {5y}^{2} + 6y - 8 = 0 \\ = > {5y}^{2} + (10 - 4)y - 8 = 0 \\ = > ( {5y}^{2} + 10y) - (4y - 8) = 0 \\ = > 5y(y + 2) - 4(y + 2) = 0 \\ = > (5y - 4)(y + 2) = 0 \\ here \: we \: get \: two \: values \: of \: y\\ (5y - 4) = 0 \\ = > 5y = 4 \\ = > y = \frac{4}{5} \: and \\ (y + 2) = 0 \\ = > y = - 2 \\ as \: we \:know \: - ve \: is \: neglisible \: so \: \\ the \: value \: y \: is \: \frac{4}{5}$

According to the question we have to find the value of x, so

$y = \frac{4}{5} \\ = > 3x + 2 = \frac{4}{5} \\ = > 3x = \frac{4}{5} - 2 \\ = > 3x = \frac{4 - 10}{5} \\ = > 3x = \frac{ - 6}{5} \\ = > x = \frac{ - 6}{ \frac{5}{3} } \\ = > x = \frac{ - 6}{5 \times 3} \\ = > x = \frac{ - 6}{15} \\ = > x = \frac{ - 2}{ 5}$