Anonymous
Anonymous asked in Science & MathematicsMathematics · 8 years ago

# Can you solve this maths equation?

X(squared)-3X-10=0

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X^2-3X-10=0

(X-5)(X+2)=0

X = 5 or -2

• X^2 - 3X -10 = 0

or , X^2 - 5X + 2X - 10 = 0

take X common in first part and 2 common second part, then

X (X - 5) + 2 (X - 5) = 0

take (x - 5) common, then

(X - 5) (X + 2) = 0

thus,

either (X - 5) = 0 or (X + 2)=0

for (X - 5) = 0 we get, X = 5

for (X + 2) = 0 we get, X = - 2

therefore X= 5 or -2

• Look for two numbers that add to -3 and their product is -10 : +2, -5

x^2 - 3x - 10 = 0

(x + 2)(x - 5) = 0

x = -2, 5

• x^2 - 3x - 10 = 0

As this is a monic equation (meaning x^2 has a value of 1) the factoring will start like this:

(x ) (x )

Now take out the sum, product and factors of the equation:

Sum = -3

Product = -10

Factors of the product = +-(1, 2, 5, 10)

Now from the list of factors you will need to find two numbers that when added together give -3 and when multiplied together give -10, -5 and 2 added together give -3 and multiplied together give -10 so plug those in

(x - 5) (x + 2) = 0

For your first solution divide both sides by (x+2):

x - 5 = 0

x = 5

For your second solution divide both sides by (x-5):

x + 2 = 0

x = -2

--------------------

Overall:

x = -2, 5

• x^2 - 3x -10 = 0

COEFFICIENT OF x^2 = +1

( +1) ( -10) = -10

FIND FACTORS OF -10 WHICH ADD UP TO - 3 ( COEFFICIENT OF x )

( +2)(-5) = -10

x^2 +2x -5x -10 = 0

x ( x+2) - 5( x+2) = 0

( x-5) ( x+2) = 0

x = 5 OR -2 ANSWER

• x^2-3x-10=0 (first step factor it:)

(x-5)(x+2)=0 (now for it to equal 0 either factor has to be 0 so:)

x = {5, -2}

x can be either 5 or -2

Source(s): This is called a quadratic equation. You can look up how to factor a quadratic equation if you don't already know how.
• really..?? oh come on.... is this how lazy you guys are?.

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