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32. If a+b: 5 and ab: 6, what is the value of a²-b²?​

User Retrodrone
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To determine the value of a² - b², we can use the identity:

a² - b² = (a + b) * (a - b)

Given that a + b equals 5 and ab equals 6, we can calculate the value of a - b:

To do this, we find a by substituting the value of b in the equation a + b = 5:

a = 5 - b

Next, we use the expression for ab and replace a with (5 - b):

(5 - b) * b = 6

Expanding and rearranging the equation, we get:

5b - b² = 6

Now, we apply the identity a² - b² = (a + b) * (a - b) and replace the values:

a² - b² = (a + b) * (a - b) = 5 * (5b - b²)

Now, we need to find the values of b that satisfy the equation 5b - b² = 6:

By factoring the quadratic equation, we get:

(b - 3)(b - 2) = 0

Setting each factor to zero and solving for b, we find two possible values for b: b = 3 and b = 2.

After obtaining the corresponding values of a:

If b = 3, then a = 5 - b = 5 - 3 = 2

If b = 2, then a = 5 - b = 5 - 2 = 3

Now, we can calculate a² - b² for each case:

When b = 3: a² - b² = 2² - 3² = 4 - 9 = -5

When b = 2: a² - b² = 3² - 2² = 9 - 4 = 5

Thus, the potential values of a² - b² are -5 and 5.

User Enfield
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