Answer:
4
Step-by-step explanation:
4+3a=16
-4. -4
3a=12
/3. /3
a=4
by the use of elimination method
make all coefficients of subject to be eliminated similar..by multiplying the coefficients with one another
for eqn(i)
5(-10y+9x=-9)
-50y+45x=-45
for eqn(ii)
9(10y+5x=-5)
90y+45x=-45
-50y+45x=-45
90y+45x=-45
...subtract each set from the other...
we get
-140y+0=0
y=0
from eqn(i)
10y+5x=-5
0+5x=-5
x= -1
I=prt. Sub in what you know: 562.50=1500(r)(5). Multiply: 562.5=7500r. Divide to get the unknown by itself: .075=r or 10%=r. :)