Question

y^2 +10y -1200=0
solve this quadratic equation? ​

Answer 1

Answer:

y^2 - 10y + 21 = 0

Simplifying

y2 + -10y + 21 = 0

Reorder the terms:

21 + -10y + y2 = 0

Solving

21 + -10y + y2 = 0

Solving for variable 'y'.

Factor a trinomial.

(3 + -1y)(7 + -1y) = 0

Subproblem 1

Set the factor '(3 + -1y)' equal to zero and attempt to solve:

Simplifying

3 + -1y = 0

Solving

3 + -1y = 0

Move all terms containing y to the left, all other terms to the right.

Add '-3' to each side of the equation.

3 + -3 + -1y = 0 + -3

Combine like terms: 3 + -3 = 0

0 + -1y = 0 + -3

-1y = 0 + -3

Combine like terms: 0 + -3 = -3

-1y = -3

Divide each side by '-1'.

y = 3

Simplifying

y = 3

Subproblem 2

Set the factor '(7 + -1y)' equal to zero and attempt to solve:

Simplifying

7 + -1y = 0

Solving

7 + -1y = 0

Move all terms containing y to the left, all other terms to the right.

Add '-7' to each side of the equation.

7 + -7 + -1y = 0 + -7

Combine like terms: 7 + -7 = 0

0 + -1y = 0 + -7

-1y = 0 + -7

Combine like terms: 0 + -7 = -7

-1y = -7

Divide each side by '-1'.

y = 7

Simplifying

y = 7

Solution

y = {3, 7}

Answer 2

$\huge\color{red}\boxed{AnSWer}$

y² + 10y - 1200 = 0

$solving \: by \: quadratic \: formula \: \\ \ \: \: \color{brown} \boxed {y =\frac{-b±\sqrt{{b}^{2}-4ac}}{2a} }$

where a = 1 b = 10 c = -1200

by putting value in formula

$x = \frac{ - 10 ± \sqrt{ {10}^{2} - 4(1) - 1200} }{2(1)} \\ \\ x = \frac{10 \: ± \sqrt{100 + 4800} }{2}$

from here two cases

case 1

$if \: \\ \\ y= \frac{ - 10 - \sqrt{4900} }{2} \\ \\ \\y= \frac{ - 10 - 70}{2} \\ \\ y = \frac{ - 80}{2} \\ \\ y = - 40 - - - - (1st \: value)$

case 2

$if \\ \\ y = \frac{ - 10 + \sqrt{4900} }{2} \\ \\ y= \frac{ - 10 + 70}{2} \\ \\ y = \frac{60}{2} \\ \\ y = 30 - - - - - (2nd \: value)$

$\huge\color{green}{expalnation}$

• we solve above value by using quadratic formula

• we get two value from formula

• both values are real

• as we know a quratic equation has all ways 2 solution or answers

• so we get two answer

$\huge\color{</strong><strong>orange</strong><strong>}{</strong><strong>extra\</strong><strong>:</strong><strong>info</strong><strong>}$

quadratic equations:- an equation having hight power of functing variable as 2

we can also find answer of this equation by factorising the mid term but it hard for me at lest

hope it helps you

be brainly