Refer to the figure.

a = 20

Step-by-step explanation:

Since HL must be perpendicular to HJ, we know that angles 2 and 3 must add up to 90 degrees.

Thus, we get a + 15 + a + 35 = 90.

Solving for a gives us a = 20.

answer: on graphs, the open and closed circles, or vertical asymptotes drawn as dashed lines us identify discontinuities.

as before, graphs and tables allow us to estimate at best.

when working with formulas, getting zero in the denominator indicates a point of discontinuity.

when working with piecewise-defined functions, check for discontinuities at the transition points where one piece ends and the next begins.

step-by-step explanation: