Use the following statements to write a compound statement for the conjunction or disjunction. then find its truth value.
p: an isosceles triangle has two congruent sides.
q: a right angle measures 90°.
r: four points are always coplanar.
s: a decagon has 12 sides.

a. four points are always coplanar and a right angle measures 90°. false.
b. four points are always coplanar and a right angle measures 90°. true.
c. four points are always coplanar or a right angle measures 90°. false.
d. four points are always coplanar or a right angle measures 90°. true.

Options b and d

Step-by-step explanation:

It's a question of Boolean's algebra

We will find the truth values of each statement p, q, r, and s first.

p : An isosceles triangle has two congruent sides.

Means truth value is True

q ; A right angle measures 90°

Truth value of this statement will be True

r : Four Points are always coplanar.

Truth value of this statement will be False.

s : A decagon has 12 sides

Truth value of the statement will be False.

Now we come to the options.

a. Four points are always coplanar and a right angle measures 90°.

Here "and" means conjunction and truth value of conjuncion of two statements will be true if only both the statements are true.

r        q         r ∧ q

T        T            T

But the truth value is given as false so not the correct option.

b. Four points are always coplanar and a right angle measures 90°.

As we have discussed in option a. truth value of the conjunction is True so this option will be the correct option.

c. Four points are always coplanar or a right angle measures 90°

OR means it's a disjunction and truth value of disjunction is false only when both the statements are False.

r         q        r ∨ q

T        T           T

But the truth value is given as False, so this option is not correct.

d. Four points are always coplanar or a right angle measure 90°

As discussed in option c. Truth value will be True. so this option will be the correct option.

Options b and d are the correct options.  

answer: 486in^2

step-by-step explanation: