Help me please I give good amount for your help

1. The first expression is the greatest.

2.a) (see below)

b) $10

Step-by-step explanation:

1

For the first expression, the negative signs cancel and since 7 is smaller than 9, we will get a number less than 1, but greater than zero.

For the second expression, since 7 is negative and 9 is not, we will get a negative number.

For the third expression, since two negative numbers are being combined, we will end up with a negative number.

For the fourth expression, since 7 is smaller than 9, we will get a negative number.

So, there is only expression that will turn out to be greater than zero (not negative), and hence its value is the greatest: the first expression.

2

a)

A tape diagram consists of three parts: the amount in each group, the number of groups, and the total number.

Here, the amount in each group is x-2, which is the total Andre makes in a week, after he donates $2 (x represents how much he's paid before donating). The number of groups represents how many weeks he'll be working, which in this case is five, and the total number, which is 40, is how much money he'll make in all.

b)

Remember that x represents how much Andre is paid before donating:

40 = (x-2)+(x-2)+(x-2)+(x-2)+(x-2)

40 = 5x -10

50 = 5x

x = 10

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.