I only know how to do # 7.
7. 4.5^2 + 6^2 = 7.5^2
20.25 + 36 = 56.25
56.25 = 56.25
yes, the card is a right triangle because A and B added together equals the same as C
Find the sale price by multiplying the original price by 70% then add the two prices together to get the total.
799 x 0.70 = 559.30
549 x 0.70 = 384.30
Total: 559.30 + 384.30 = $943.60
This is true, because there is an infinite amount of real numbers in both, and they are both countably infinite (so these infinities are equal). Hope this helps!
Y= -6 --> plug this -6 into the y of the 2nd equation
y= 4x+12 --> -6 = 4x+12 --> 4x = -18
x = -18/4 = -9/2 --> now this is the x solution coordinate, and we know that y must equal -6 from the 1st equation, so our solution point is:
(-9/2, -6)
Hope that helped!
