Explanation for Question 27 From the Math (Calc) Section on the 2019 March Sat
Question 27 says in the equation above a is a constant for 2 what value of a does the equation have infinitely many solutions. 3 So for this equation have infinitely many solutions. 4 We're going to have to get the same exact values on the left and 5 right side as coefficients for X. 6 So let's rewrite this and solve and we'll see under what circumstances 7 that would happen. So first we're just going to add 8 and subtract like turns. So I'm going to distribute a X plus negative 9 12 plus negative eight X is equal to negative 12. 10 The negative twelves cancel. If I add 12 to both sides. 11 And then if I add eight XTO side, 12 I get a X is equal to eight X. 13 So for this equation to have infinitely many solutions, 14 these coefficients would have to be the same value. 15 So that means a would need to equal eight. 16 So the answer to this question is answered D.