Did i calculate correctly? for exercises 3-6, solve the systems using the addition method. [question 4] 5a + 6b = -8 7a - 3b = 23 i chose to eliminate equation b. i multiplied the equation by two to eliminate b. 5a + 6b = -8 14a - 6b = 46 19a + 0 = 38 divide by 19 19a/19= a 38/19= 2 so [a] would equal 2. now i solve for b. 5(a)+6b= -8 10+6b= -8 -10 = -10 6b= -18 6b/6 = -18/6 b= -3 so [b] is equal to -3. my answer for question four is: (2, -3).

good job, you solved it correctly! \(^o^)/

if she was to only spend a dollar she can get 1lb

step-by-step explanation:

there is only one way to arrange all the eight relative to each other because they are not distinct. we have

now there are nine places to place an (and not more than one in one place).   because we have four symbols, we need to choose four of these nine places to insert an . order does not matter because the are not distinct.

thus there are 1 · c(9,4) ways, or, if we calculate it,

thus there are 126 ways to form such "words."