(7 - 2i)(8 + 9i)
= 7(8 + 9i) + -2i(8 + 9i)
= 56 + 63i + -16i - 18i²
= 56 + 47i +18 <em> (NOTE: i² = -1 → (-18)(-1) = +18)</em>
= 74 + 47i
Answer: 74 + 47i
Answer:
(10-2)÷4.
Step-by-step explanation:
We are to select the correct expression that represents a number that is one fourth as great as 10-2.
Let the required number be represented by x.
Given:
28/36 ratio
annual income: 86,250
28+36 = 64
28/64 * 86,250 = 0.4375 * 86,250 = 37,734.375
36/64 * 86,250 = 0.5625 * 86,250 = 48,515.625
28/36 ⇒ 37,734.375/48,515.625
Leah spent $6 more than Janine.
Janine spent $15.
Leah spent 21 dollars
answer
5
set up equations
daren is 3 years older than tom
D = 3 + T
3 years ago leah will be 14 less than 3 times darren's age
L - 3 = 3(D - 3) - 14
L - 3 = 3D - 9 - 14
L = 3D - 9 - 14 + 3
L = 3D - 20
5 years ago, leah was 2 years less than 2 times tom
L - 5 = 2(T - 5) - 2
L - 5 = 2T - 10 -2
L = 2T - 10 - 2 + 5
L = 2T - 7
find leah's current age
set L = 3D - 20 and L = 2T - 7 equal to each other
3D - 20 = 2T - 7
plug 3 + T into D using the equation D = 3 + T
3D - 20 = 2T - 7
3(3 + T) - 20 = 2T - 7
9 + 3T - 20 = 2T - 7
T = - 7 - 9 + 20
T = 4
plug T back into L = 2T - 7 to find leah's current age
L = 2T - 7
L = 2 * 4 - 7
L = 8 - 7
L = 1
leah's age 4 years from now
add 4 to leah's current age
1 + 4 = 5
