If there are 4 times as many shurbs as trees, then in total, we should split it into 5 parts. So we should divide 40 by 5. That gives us 8, so there are 8 trees. Shrubs is 4 times as much, so there are 8 times 4 shrubs which is 32 shrubs.
When you add 5 and -6, you get -1. When they are multiplied, you get -30. I just did this by finding all of the factors that went into 30 and making one negative.
