Answer:
12a - 6b
Step-by-step explanation:
Given
8a + 3b + 4a - 9b ← collect like terms
= (8a + 4b) + (3b - 9b)
= 12a + (- 6b)
= 12a - 6b
-3/4x + 5/6 y = 15
Multiply through by 6
-9/2x + 5y = 90
Add 9/2x to both sides
5y = 90 + 9/2x
Divide both sides by 5
y = 18 + 9/10x
y = 9/10x + 18
Comparing with the general equation of a straight line y = mx + c
Gradient (m) = 9/10 or 0.9
and the y - intercept (c) = 18
Answer:
Step-by-step explanation:
shape Sides Sum of interior angles Each Angle
Triangle 3 180° 60°
Quadrilateral 4 360° 90°
Pentagon 5 540° 108°
Hexagon 6 720° 120°
Heptagon 7 900° 128.57...°
Octagon 8 1080° 135°
Nonagon 9 1260° 140°
13 is what i think
3 divided by 2= 1.5
1.5*9=13.5 and you can't score half a point so the answer is 13
