Solve the Problem Using Matrices ${ } ^ { \circ } \mathrm { F }$

Multiple Choice

Solve the problem using matrices.
-In a study of heat transfer in a grid of wires, the temperature at an exterior node is maintained at a constant value (in ${ } ^ { \circ } \mathrm { F }$ ) as shown in the figure. When the grid is in thermal equilibrium, the temperature at an interior node is the average of the temperatures at the four adjacent nodes. For instance $T _ { 1 } = \frac { 0 + 0 + 300 + T _ { 2 } } { 4 }$ , or $4 T _ { 1 } - T _ { 2 } = 300$ . Find the temperatures $T _ { 1 } , T _ { 2 }$ , and $T _ { 3 }$ when the grid is in thermal equilibrium.

A) $\mathrm { T } _ { 1 } = \frac { 674 } { 7 } { } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 2 } = \frac { 596 } { 7 } { } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 3 } = \frac { 85 } { 2 } { } ^ { \circ } \mathrm { F }$
B) $\mathrm { T } _ { 1 } = \frac { 1348 } { 7 } { } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 2 } = \frac { 596 } { 7 } { } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 3 } = 85 ^ { \circ } \mathrm { F }$
C) $\mathrm { T } _ { 1 } = \frac { 764 } { 7 } { } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 2 } = \frac { 956 } { 7 } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 3 } = \frac { 400 } { 7 } \circ { } ^ { \circ } \mathrm { F }$
D) $\mathrm { T } _ { 1 } = \frac { 664 } { 7 } { } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 2 } = \frac { 556 } { 7 } { } ^ { \circ } \mathrm { F } , \mathrm { T } _ { 3 } = \frac { 645 } { 7 } ^ { \circ } \mathrm { F }$