A) 4(25-3y)+5y=9
100-7y=9
91=7y
y=13
(-14,13)
b) 14-x=x-10
2x=24
x=12
(12,14)
c) 4x=12
(3,7)
d) 18.5x+10.4y=200
x+y=130
Answer:

Step-by-step explanation:
-The locust population grows by a factor and can therefore be modeled by an exponential function of the form:

Where:
is the population after t days.
is the initial population given as 7600
is the rate of growth
is time in days
-Given that the growth is by a factor of 5( equivalent to 500%), the r value will be 5
-The population increases by a factor of 5 every 22 days. therefore at any time instance, t will be divided by 22 to get the effective time for calculations.
Hence, the exponential growth function will be expressed as:

For example:
(4/9) x=8
Now can solve this equation multiplying each side by 9/4.
(9/4)(4/9)x=(9/4)8
x=18
To check:
(4/9)(18)=(4*18)/9=72/9=8
In
,
$a$ is the real part
$ib$ is the imaginary part.
Comparing, we get:
Real part: $91$
Imaginary part: $-27i$
Answer: (f times g)(x)=(9x+1) times x³=9x⁴+x³
Step-by-step explanation: