Question

what is the value of u? write your answer as an integer or as a decimal rounded to the nearest tenth.

Explanation:

Step1: Use exterior - angle property

The exterior - angle of a triangle is equal to the sum of the two non - adjacent interior angles. So, $39u + 24=(11u + 45)+43$.

Step2: Simplify the right - hand side

$(11u + 45)+43=11u+88$. So the equation becomes $39u + 24=11u + 88$.

Step3: Subtract $11u$ from both sides

$39u-11u + 24=11u-11u + 88$, which simplifies to $28u+24 = 88$.

Step4: Subtract 24 from both sides

$28u+24 - 24=88 - 24$, resulting in $28u=64$.

Step5: Solve for $u$

$u=\frac{64}{28}=\frac{16}{7}\approx2.3$.

Answer:

$2.3$