The ratio of money in Brian's wallet to Colin's wallet one day was 7:2. Brian spent £39 that day.
Brian now had £4 less than Colin.
How much did they initially have altogether?

Leo is going to use a random number generator 4 0 0 400 times. each time he uses it, he will get a 1 , 2 , 3 , 4 , 1,2,3,4, or 5 5. what is the best prediction for the number of times that leo will get an odd number?

What is the answer to this question? i'm a bit stumped. also how do i do it? 5(x - 4) = 2(x + 5)

Ab and bc form a right angle at point b. if a= (-3,-1) and b= (4,4) what is the equation of bc?