Question

1)The teacher tells the class that the highest marks obtained by a student in a
class is twice the lowest marks plus 7. The highest score is 87. (Take the lowest score to be l )

2) In an isosceles triangle, the vertex angle is twice either base angle. (Let the base
angle be b in degrees. Remember that the sum of angles of a triangle is 1
degrees)​

Answer 1

Answer:

1 Answer

Let's assume the lowest mark is ′ x ′ .

twice the lowest mark will be 2x

given that twice the lowest marks plus seven is highest mark.

=> 2x+7=87

=>2x=80

=>x=40

Hence the lowestmark is 40.

2 As we already know that the base angles in an isosceles triangle are equal. Now, let us assume the base angle of the isosceles triangle as b. Now, from the condition that the sum of angles in a triangle is 180∘. Hence, the base angle of the given isosceles triangle is 45∘ and the vertex angle is 90∘.

otherwise

Let the base angle =b

⇒vertex angle =2b

Sum of angles in a triangle =180 °

⇒b+b+2b=180

⇒b=45 °

Angles =(45 °,45 °,90°)

Answer 2

Answer:

1 Answer

Let's assume the lowest mark is ′ x ′ .

twice the lowest mark will be 2x

given that twice the lowest marks plus seven is highest mark.

=> 2x+7=87

=>2x=80

=>x=40

Hence the lowestmark is 40.

2 As we already know that the base angles in an isosceles triangle are equal. Now, let us assume the base angle of the isosceles triangle as b. Now, from the condition that the sum of angles in a triangle is 180∘. Hence, the base angle of the given isosceles triangle is 45∘ and the vertex angle is 90∘.

otherwise

Let the base angle =b

⇒vertex angle =2b

Sum of angles in a triangle =180 °

⇒b+b+2b=180

⇒b=45 °

Angles =(45 °,45 °,90°)