Find the zeroes of the quadratic polynomial x2+7x+10x^2 + 7x + 10, and verify the relationship between the zeroes and the coefficients.

Answer: The zeroes of the quadratic polynomial x2+7x+10x^2 + 7x + 10 are −2-2 and −5-5. The relationship between the zeroes and coefficients is verified as the sum of zeroes (−2+(−5)=−7)(-2 + (-5) = -7) equals −ba(−71=−7)-\frac{b}{a} (-\frac{7}{1} = -7) and the product of zeroes ((−2)×(−5)=10)((-2) \times (-5) = 10) equals ca(101=10)\frac{c}{a} (\frac{10}{1} = 10).

Step-by-step solution

Step 1: Factor the quadratic polynomial

To find the zeroes of the quadratic polynomial, we need to set the polynomial equal to zero and solve for xx. We can factor the quadratic expression by finding two numbers that multiply to 1010 and add up to 77. These numbers are 22 and 55.

Step 2: Factor the expression

We rewrite the middle term 7x7x as 2x+5x2x + 5x. Then, we factor by grouping. We take out the common factor xx from the first two terms and 55 from the last two terms. This results in the factored form (x+2)(x+5)=0(x+2)(x+5)=0.

Step 3: Find the zeroes

For the product of two factors to be zero, at least one of the factors must be zero. So, we set each factor equal to zero and solve for xx to find the zeroes of the polynomial. The zeroes are x=−2x = -2 and x=−5x = -5.

Step 4: Identify coefficients

For a general quadratic polynomial ax2+bx+cax^2 + bx + c, we identify the coefficients. In our case, for x2+7x+10x^2 + 7x + 10, we have a=1a=1, b=7b=7, and c=10c=10.

Step 5: Verify sum of zeroes

The sum of the zeroes of a quadratic polynomial ax2+bx+cax^2+bx+c is given by the formula −ba-\frac{b}{a}. We calculate the sum of the zeroes we found, −2+(−5)=−7-2 + (-5) = -7, and compare it with −ba-\frac{b}{a}. Both values are −7-7, so the relationship is verified.

Step 6: Verify product of zeroes

The product of the zeroes of a quadratic polynomial ax2+bx+cax^2+bx+c is given by the formula ca\frac{c}{a}. We calculate the product of the zeroes we found, (−2)×(−5)=10(-2) \times (-5) = 10, and compare it with ca\frac{c}{a}. Both values are 1010, so the relationship is verified.

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