Question

Given b = 4 and c = -5, evaluate b 2 - c 2.


41
-2
-9

Answer 1

When you square c, don't forget to square the negative as well!
\[\Large \color{orangered}{b}^2-\color{orangered}{c}^2\qquad\to\qquad \color{orangered}{4}^2-\color{orangered}{(-5)}^2\]What's (-5)^2? :)

Answer 2

$$\huge b^2-c^2= (b+c)(b-c)$$

Answer 3

that would be 25

Answer 4

Good good good.\[\Large 4^2-25\]

Answer 5

Understand how to finish it up? :D

Answer 6

so -9

Answer 7

yay good job \c:/

Answer 8

what about
Given a = -3, b = 4 and c = -5, evaluate ab + c.

Answer 9

Substitute the given values for the variables
ie replace a with -3,
b with 4
and
c with -5.

Answer 10

When you substitute a negative value, it might help to add brackets. That might make it a little less confusing.
\[\Large a=-3\]\[\Large ab+c \qquad\to\qquad (-3)b+c\]Understand how I plugged in the value for \(\Large a\) ?
Try to do the same with the c term, adding the brackets.