Answer:
Option (3)
Step-by-step explanation:
By applying cosine rule in the triangle ABC,
BC² = AC² + AB² - 2(AC)(AB)cosA
5² = 3² + 7²- 2(3)(7)cosA
25 = 9 + 49 - 42cos(A)
25 = 58 - 42cos(A)
cos(A) = 
A = 
A = 38.21°
A ≈ 38°
Option (3) will be the correct option.
A triangle has 180 degrees. You can find the total sum of the ratio by adding its parts together 1+3+5 = 9 Now to find out what each part of the ratio is worth we divide the whole value (180) by the sum of the ratio parts (9)
180/9 = 20
Now we multiply each part of the ratio by 20
1 * 20 = 20
3 * 20 = 60
5 * 20 = 100
Since we have an angle greater than 90 degrees this is an obtuse triangle.
Answer: y= 3x-1
Step-by-step explanation:
Equation of a straight line:
y = mx + b ------(i)
Step by Step Solution:
Step 1: Calculating Slope (m).
m =
y2-y1
x2-x1
m =
2--1
1-0
m =
3
1
m = 3
Now putting value of m in equation (i)
y = 3x + b -----(ii)
Step 2: Calculating Y-intercept (b).
Lets choose the first point, (0,-1) for calculating y-intercept:
y = mx + b
-1 = 3(0) + b
-1 = 0 + b
-1 = b
b = -1
