Question

Twice Brittany’s age is less than the age of Abraham Lincoln when he died. President Lincoln was 56 years old at the time of his death. Write an inequality to represent Brittany’s age, b. Brittany’s brother, Nate, is two years younger than Brittany. Write an equation for Nate’s age, n, in terms of Brittany’s age, b. Rewrite the expression from Part B to get the variable b alone on one side of the equation. (This is also called isolating b.) Substitute the value of b from Part C into the inequality you found in Part A. Solve the inequalities from parts A and D for the variables b and n, respectively. Could Brittany be 27 years old and Nate 26? Why or why not?

Answer 1

2b < 56

n = b - 2

b = n + 2

n < 27

b < 28

No, because the difference between Brittany and Nate's age is 2years

Explanation:

A.)

Twice Brittany’s age is less than the age of Abraham Lincoln when he died. President Lincoln was 56 years old at the time of his death

Let Brittany's age = b

Twice Brittany's age = 2 × b = 2b

Lincoln's age = 56

2b < 56

B.)

Nate's age = n

Nate is 2 years younger than brittany who is aged 'b'

n = b - 2

C.) b = n + 2

D.)

If 2b < 56 and b = n + 2

2(n + 2) < 56

2n + 2 < 56

2n < 56 - 2

2n < 54 ; n < 27

2b < 56

b < 56/2

b < 28

No, because the difference between Brittany and Nate's age is 2years