How do I solve fraction equations
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Empty box + box + empty box fill in the box is equal to 30 how

Write a polynomial function f of least degree that has rational coefficients, a leading coefficient of 1, and the given zeros. 3, 4+2i, 1+(sqrt)7 the answer is supposed to be: f(x)=x(^5)-13x(^4)+60x(^3)-82x(^2)-144x+360 what am i doing wrong?

What is the y-intercept of the line with the equation 3x + 4y = 12?