9514 1404 393
Answer:
(a) 42.3°
Step-by-step explanation:
Side 'a' is the shortest of three unequal sides, so angle A will be the smallest angle in the triangle. Its measure can be found from the Law of Cosines.
a² = b² +c² -2bc·cos(A)
cos(A) = (b² +c² -a²)/(2bc) = (21² +25² -17²)/(2·21·25) = 777/1050
A = arccos(777/1050) ≈ 42.3°
The measure of angle A is about 42.3°.
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<u><em>Additional comment</em></u>
The smallest angle in a triangle can never be greater than 60°. This lets you eliminate choices that exceed that value.
There will be 1.078x students next year and equation is number of students in next year = x + 7.8% of x
<h3><u>Solution:</u></h3>
Given, There are "x" number of students at helms.
The number of students increases by 7.8% each year which means if there "x" number of students in present year, then the number of students in next year will be x + 7.8% of x
Number of students in next year = number of students in present year + increased number of students.

Thus there will be 1.078x students in next year
Answer:
-3
Step-by-step explanation:
You could turn the fraction into a decimal and then see which is bigger
x=9 because the triangle is equilateral which means every side is equal to 60. When you do the math you get 7x-3=60 which is 7x=63 and 63/7=9