How do you factor ${{y}^{2}}-2y-3$ ?
Answer
617.1k+ views
Hint: In this question, we have to find the factors of the equation. A quadratic equation is given in the problem, so we will apply splitting the middle term method to get the factors for the same. We start solving this problem by finding two numbers such that the product of the two numbers is equal to the product of the coefficient of ${{y}^{2}}$ and the constant. Also, the sum of these two numbers is the coefficient of y. Thus, after finding these 2 numbers, we split the middle term as the sum of those two numbers and make the necessary calculations to get the required solution.
Complete step by step solution:
According to the question, we have to find the factors of the quadratic equation.
Thus, we will use splitting the middle term method to get the solution.
The quadratic equation given to us is ${{y}^{2}}-2y-3$ -------- (1)
As we know, the general form of quadratic equation is $a{{y}^{2}}+y+c$ -------- (2)
Thus, on comparing equation (1) and (2), we get a=1, b=-2, and c=-3
To factorize, we have to find two numbers m and n such that $m+n=b=-2$ and $mn=a.c=1.(-3)=-3$ .
We see that if $m=-3$ and $n=1$ , then we get $m+n=-3+1=-2=b$ and $mn=a.c=-3.(1)=-3$
So, we will split the middle term as the addition of -3y and y because $-3y+1y=-2y$ , thus we get
$\Rightarrow {{y}^{2}}-3y+y-3$
Now, take common y from the first two numbers and 1 from the last two numbers, we get
$\Rightarrow y\left( y-3 \right)+1\left( y-3 \right)$
So, we will take (y-3) common on both LHS and RHS of the addition sign, we get
$\Rightarrow \left( y-3 \right)\left( y+1 \right)$
Therefore, for the quadratic equation ${{y}^{2}}-2y-3$ , its factors are $\left( y-3 \right)\left( y+1 \right)$ .
Note: Do mention all the steps properly to avoid confusion and mathematical error. You can also use the Hit and Trial method, the cross multiplication method or the Discriminant formula to get the solution for the problem.
Complete step by step solution:
According to the question, we have to find the factors of the quadratic equation.
Thus, we will use splitting the middle term method to get the solution.
The quadratic equation given to us is ${{y}^{2}}-2y-3$ -------- (1)
As we know, the general form of quadratic equation is $a{{y}^{2}}+y+c$ -------- (2)
Thus, on comparing equation (1) and (2), we get a=1, b=-2, and c=-3
To factorize, we have to find two numbers m and n such that $m+n=b=-2$ and $mn=a.c=1.(-3)=-3$ .
We see that if $m=-3$ and $n=1$ , then we get $m+n=-3+1=-2=b$ and $mn=a.c=-3.(1)=-3$
So, we will split the middle term as the addition of -3y and y because $-3y+1y=-2y$ , thus we get
$\Rightarrow {{y}^{2}}-3y+y-3$
Now, take common y from the first two numbers and 1 from the last two numbers, we get
$\Rightarrow y\left( y-3 \right)+1\left( y-3 \right)$
So, we will take (y-3) common on both LHS and RHS of the addition sign, we get
$\Rightarrow \left( y-3 \right)\left( y+1 \right)$
Therefore, for the quadratic equation ${{y}^{2}}-2y-3$ , its factors are $\left( y-3 \right)\left( y+1 \right)$ .
Note: Do mention all the steps properly to avoid confusion and mathematical error. You can also use the Hit and Trial method, the cross multiplication method or the Discriminant formula to get the solution for the problem.
Recently Updated Pages
A Paragraph on Pollution in about 100-150 Words

What is BLO What is the full form of BLO class 8 social science CBSE

10 examples of friction in our daily life

Draw a diagram of nephron and explain its structur class 11 biology CBSE

Write structures of the following compounds i 2 Chloro3methylpentane class 11 chemistry CBSE

XIX+XXX A 49 B 51 C 55 D 44 class 5 maths CBSE

Trending doubts
Explain the Treaty of Vienna of 1815 class 10 social science CBSE

1 GB equals how many MB?

10 examples of evaporation in daily life with explanations

What is the full form of POSCO class 10 social science CBSE

Which is the hottest planet in the Solar system A Earth class 10 social science CBSE

Name any four life processes in living things class 10 biology CBSE

