Question

Find the value of a for which the given pair of linear equations ax +9y + 10 = 0 and
12x + 12xy + 3a - 31 = 0 has infinite solutions
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Answer 1

Let's solve for a.

$→12x+12xy+3a−31=0$

Step 1: Add -12xy to both sides.

$12xy+3a+12x−31+−12xy=0+−12xy$

$3a+12x−31=−12xy$

Step 2: Add -12x to both sides.

$3a+12x−31+−12x=−12xy+−12x$

$3a−31=−12xy−12x$

Step 3: Add 31 to both sides.

$3a−31+31=−12xy−12x+31$

$3a=−12xy−12x+31$