Question

Offering brainliest if answered with explanation

Answer 1

Answer:

Step-by-step explanation:

we know that the 3 sides add up to the perimeter of 18cm. We can use this to find the length of the 3rd side, CA.  

AB + BC + CA = 18

7 + 3 + CA = 18

10 + CA = 18

CA = 8

The pythagorean theorem states that in a right triangle a2 + b2 = c2, where c is the length of the hypotenuse (the longest side opposite to the right angle) and a and b are the lengths of the other two sides.  

In this problem we can replace a with 7, the length of AB, b with 3, the length of BC, and c with 8, the length of CA.  

a2 + b2 = c2

72 + 32 = 82

49 + 9 = 64

58 = 64

Since the equation is not true, we can deduce that ABC is NOT a right triangle start, we know that the 3 sides add up to the perimeter of 18cm. We can use this to find the length of the 3rd side, CA.  

AB + BC + CA = 18

7 + 3 + CA = 18

10 + CA = 18

CA = 8

The pythagorean theorem states that in a right triangle a2 + b2 = c2, where c is the length of the hypotenuse (the longest side opposite to the right angle) and a and b are the lengths of the other two sides.  

In this problem we can replace a with 7, the length of AB, b with 3, the length of BC, and c with 8, the length of CA.  

a2 + b2 = c2

72 + 32 = 82

49 + 9 = 64

58 = 64

Since the equation is not true, we can deduce that ABC is NOT a right triangle start, we know that the 3 sides add up to the perimeter of 18cm. We can use this to find the length of the 3rd side, CA.  

AB + BC + CA = 18

7 + 3 + CA = 18

10 + CA = 18

CA = 8

The pythagorean theorem states that in a right triangle a2 + b2 = c2, where c is the length of the hypotenuse (the longest side opposite to the right angle) and a and b are the lengths of the other two sides.  

In this problem we can replace a with 7, the length of AB, b with 3, the length of BC, and c with 8, the length of CA.  

a2 + b2 = c2

72 + 32 = 82

49 + 9 = 64

58 = 64

Since the equation is not true, we can deduce that ABC is NOT a right triangle

Answer 2

Answer:

ABC is not a right triangle.

Step-by-step explanation:

The perimeter of a triangle is the sum of all its sides(easier to see if you draw it):

P = AB + BC + AC

We can substitute the values we have:

18 = 7 + 3 + AC

18 = 10 + AC

AC = 8

In a right triangle, the hypotenuse is always the largest side and is equal to the square root of the squares of the legs by the pythagorean theorem(a^2 + b^2 = c^2). Our largest side is 8, so we would set that as equal to the hypotenuse:

8^2 = 7^2 + 3^2

64 = 49 + 9

64 = 58

64 is not equal to 58, so triangle ABC is not a right triangle.