-7x-5y=-47x+9y=-4
combine like terms to cross out the 7x
solve for y, to get -2
plug it back in to one of the equations and x is 2
y=-2
x=2
Answer:
30,240 ways, if I am restricted to using A, B, and C for letters
Step-by-step explanation:
This uses Combinatorics from Discrete Math.
so.
3 letters and 4 digits.
26 letters from alphabet, but you want to choose first letters. no repeats...
Does this mean only letters A, B, and C ?
digits from 10 digits...
I imagine 7 empty slots , and the number of ways they occur together is by the product of the number of choices each box has.
3*2*1 * 10*9*8*7 = 6 * 5040 = 30,240 ways
Answer:
Step-by-step explanation:
∠ABD is the sum of the angles ∠ABC and ∠CBD. In other words:
Substitute in known values:
And subtract. Hence:
In conclusion, ∠ABC measures 34°.
