The point a(4,10) is reflected across the x axis. where is a?

Reflection across the x-axis puts the image point as far below the x-axis as the original is above. That is, it changes the sign of the y-coordinate.

The image of A(4, 10) is A'(4, -10).

Selection c. (4, -10) is appropriate.

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116