3. tell which number is prime: 18, 42, 68, 79. 4.find the value of the expression 48 8 + 4 x 4. 5.evaluate (c − b)2 + a2 for a = –5, b = –2, and c = –4.

1) 79

2) 400

3) 29

Step-by-step explanation:

1) To find : Tell which number is prime: 18, 42, 68, 79.

Solution :

A prime number is defined as number which is only divisible by 1 and itself.

As 18,42 and 68 were divisible by 2.

But 79 is not divisible by any number.

Which means 79 is the only prime number which is divisible by 1 and itself.

2) To find : The value of the expression

Solution :

The expression,

Therefore,

3) Evaluate : for a=-5, b=-2 and c=-4

Solution :

The expression is

Substitute the values, a=-5, b=-2 and c=-4

a. the are of the rectangle is 18.25

b. 18.25 times two is 36.50

rae me : d