the answer is 3
but a way to work these problems out is to use PEMDAS
p-parentheses
e-exponent
m-multiplication
d-division
a-addition
s-subtraction
they have to be donr in that order or the answer will come out different
So heterozygous means one dominant trait and one recessive trait (Ll). Homozygous is either 2 recessive traits or 2 dominat. (in this case ll).
1.)Genotype: Ll and ll
Phenotype: 50% chance of Long pea plant, 50% chance of short.
2.) Genotype: Ww (widows peak) and ww (no widows peak)
Phenotypes: 75% chance of widows peak and 25% of no widows peak.
3.) Genotype: BB and Bb
Phenotype: 100% chance of black
There are many ways to solve simultaneous linear equations. One of my favorite for finding integer solutions is graphing. The attached graph shows the solution to be ...
... (x, y) = (4, 7)
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You can also use Cramer's Rule, or the Vedic math variation of it, which tells you the solution to

is given by

Here, that means
... x = (9·67-5·75)/(9·8-5·3) = 228/57 = 4
... y = (75·8-67·3)/57 = 399/57 = 7
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A (graphing) calculator greatly facilitates either of these approaches.
(-2.3)*4.7 would be equal to -10.81