-3 3/4 + 1/2 on a number line

Find the gradient of f(x, y,z)equals=left parenthesis x squared plus y squared plus z squared right parenthesis superscript negative 1 divided by 2 baseline plus ln left parenthesis x right parenthesis x2+y2+z2−1/2+ln(xyz) at the point left parenthesis negative 2 comma 1 comma negative 2 right parenthesis(−2,1,−2).

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.

What is the equation of the line that is parallel to the line with the equation y= -3/4x +1 and passes through the point (12,-12)