Answer:
9a + 6b
Step-by-step explanation:
4a+7b+5a-b = 9a + 6b
Free movie, F = 87pts
Initial reward, I = 10pts
Additional reward, A = 7pts
Movie visit, X
F = I + XA
87 = 10 + 7X
X = (87-10)/7
X = 11
After 11 movie visits Andrew will have enough points for a free movie.
The first thing to do is identify the unnecessary information (that they met 2 years ago).
From there, let's go back three years ago. We'll call Daniel's age x, and Ben's age will be 3x. Ben's age is also equal to x + 20.
3x = x+ 20
2x = 20
x = 10
Daniel was 10 three years ago, and Ben was 30. Now, Ben is 33.
8. complementary angles = 90°
3x+3+10x-4 = 90
13x-1 = 90
13x = 91
so x = 91/13= 7
then K = 3(7)+3 = 24°
so L = 10(7)-4 = 70-4 = 66°
9. P is three less than twice of Q
so P = 2Q-3
supplementary angles = 180°
P+Q = 180
(2Q-3)+Q = 180
3Q-3 = 180
3Q = 183
so Q = 183/3 = 61°
then P= 2(61)-3 = 122-3 = 119°
10. B is two more than three times of C so B= 3C+2
complementary angles = 90°
B+C= 90
(3C+2)+C=90
4C+2=90
4C= 88
so C= 22°
then B = 3(22)+2= 66+2 = 68°