Answer:
(2.4, -1.2)
Step-by-step explanation:
Start by moving the x and the y to the same side and moving the number across the equal sign in both equations. We should now have y-0.45x=-2.3 and 2y+4.2x=7.8. We can use the elimination method by multiplying the first equation by -2 to get -2y+0.9x=4.6 and 2y+4.2x=7.8. From there, add the two equations together, eliminating y (-2+2=0). We now have 5.1x=12.4; divide both sides by 5.1 to get x=2.4. Then, in any of the two equations, let's use y-0.45x=-2.3, substitute x with 2.4. Now we have y-1.08=-2.3. Add 1.08 to both sides to get y=-1.22; round that to the nearest tenth to get -1.2.
Answer:
A. 0.69
Step-by-step explanation:
We need to use cosine theorem:
c²=a²+b² - 2ab* cos(θ)
c=8, a=7, b=11
8² = 7²+11² - 2*7*11 *cos(θ)
64 = 49 + 121 - 154*cos(θ)
64 - 170 = - 154*cos(θ)
- 106/ (- 154) = cos(θ)
cos(θ) = 0.69
20 pounds of lollipops. 20 x .95 = 19, 10 x 1.1 = 11. sorry i'm awful at explaining math.
Yes and no, (4, 5) multiplied by 2 is (10, 8) but reversed. It depends on how you look at it because (10, 8) would be on the other side of the graph than (8, 10) which is the actually equivalent.