Which numerical expression reprensents 1/2 the sum of 7 and 5 ?

Which shows the correct substitution of the values a,b and c from the equation 1=-2x+3x^2+1

Write each of the following numerals in base 10. for base twelve, t and e represent the face values ten and eleven, respectively. 114 base 5 89t base 12

Isabel graphed the following system of equations. 2x – y = 6 y = -3x + 4 she came up with the solution (2,-2). what were the 3 steps she did to get that solution? (make sure they are in the correct order)