The trinomial form ax2 +bx + c is a quadratic form.
Here , We need to bring in zero pairs because we need to get the roots of that quadratic equation.
The roots is referred to as the solutions or the possible value of x to make the equation true.
If the value of c is negative, you would need zero pairs to model the factorization of the polynomial.
The x-tiles on the board determine what the constants are in the factors. The product of these constants is equal to the value of c, so you would need positive tiles on one side of the x-squared tile and negative x-tiles on the other side to have opposite signs on the constants.
Opposite signs on the constants will result in a negative value for c when multiplying the factors.
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