Answer: 14x^2 - 84x - 7
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Step-by-step explanation:
The like terms 6x^2 and 8x^2 combine to 14x^2
The like terms -8x and -76x combine to -84x
Nothing pairs with the -7, so its stays as is.
Standard form is where we list the terms in decreasing exponent order. We can think of -84x as -84x^1 and the -7 as -7x^0. So 14x^2 - 84x - 7 would be the same as 14x^2 - 84x^1 - 7x^0. The exponents count down: 2,1,0.
The final answer is a trinomial since it has three terms. It is also a quadratic because the degree (highest exponent) is 2.