SAT Mc Graw Hill 2011

4. 45 SinceAB

–––

andAD

–––

are tangents to the circle,

they are perpendicular to their respective radii, as

shown. The sum of the angles in a quadrilateral is

360 °, so

m+ 3 m+ 90 + 90 = 360

Simplify: 4 m+ 180 = 360

Subtract 180: 4 m= 180

Divide by 4: m= 45

A C

D

B

m° 3 m°

5. 8 Draw the segments shown. Choose point Eto
   make rectangle ACDEand right triangle AEB.
   Notice that CD=AE,because opposite sides of a
   rectangle are equal. You can find AEwith the
   Pythagoreantheorem:
   (AE)^2 + 62 = 102
   Simplify: (AE)^2 + 36 = 100
   Subtract 36: (AE)^2 = 64
   Take the square root: AE= 8
   SinceCD=AE, CD=8.

C

A

B

D

2

2

6

2 8

E

404 McGRAW-HILL’S SAT